Trending tartwiches

These are some of those “as seen on TikTok or Instagram” sort of sandwiches.

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Read Time: 8 minutes

I made a bunch of different sandwiches in the making of this blog post. Most of them worked but some of them did not. Typically, here is where I try to convince you that I made all of these sandwiches within one week, but you might gather from the number of photos, there’s no way I accomplished that. This took more than a week off and on to test and make the three different sandwiches based on one central concept that I’m presenting. Get yourself ready.

The trending topic of tarts

Over the past few weeks, I have seen a lot of content on Instagram that was related to, replicating, or copying an upside-down French onion tart concept. I believe that the first Instagram of this sort from @lilygbakes might have been one of the original instigators of the concept, but the first one I saw was from @thenaughtyfork (that credits @lilygbakes). Both Instagram reels are just below if you haven’t seen them.

The gist of this upside-down tart is to place onions, seasoned with oil, balsamic vinegar, salt, pepper, and herbs on a sheet pan, topped with cheese and puff pastry, and bake that in the oven. The dough turns golden brown and crispy and when you flip it over, you see that the onion has softened and caramelized a bit and the cheese is melty. This tart technique is presented as a super easy-to-prepare side dish or snack and has clearly generated a lot of interest since I’ve seen a whole bunch of different versions of this concept of an upside-down, baked tart all over Instagram.

So I decided to take the concept of using store-bought dough, onions, and a baking sheet in the oven to prepare the bread for three different types of sandwiches. Keep scrolling to learn what I got into.

What are we doing?

We are making three different sandwiches based on the French onion tart concept and for no particular reason, I am presenting them in the order in which I made them. We’re going to be making sandwiches for dinner, breakfast, and then lunch last. Let’s pretend we start this sandwich adventure at night and then work our way through to lunch the next day.

Three different doughs – dinner, breakfast, and lunch

The original onion tart concept uses store-bought puff pastry but I’m using three different types of dough for my versions of these sandwiches. Once you have the dough, the concept is very similar. I’m using pizza dough, biscuit dough, and then croissant dough and two of them are store-bought and the third could be store-bought if you prefer.

Note: I filmed short videos of the making of all three of these sandwiches and will be sharing them on my Instagram throughout the week. I will link them all here if you’re reading this in the far future.

Let’s make some sandwiches!


Pizza dough sandwich

This was the first sandwich I attempted to work on. I know the original trending topic used puff pastry—which I love—but I felt for my concept that this would mean that I would be eating two large, buttery, and rich pieces of puff pastry stacked on top of each other. I decided that a thinner pizza dough would be easier and a bit less rich to tackle as the two slices of bread in this sandwich so that’s what I did.

This is Pillsbury pizza dough. The kind in the cardboard tube. Olive oil, balsamic vinegar, salt, pepper, onions, and cheese make up the additions to the dough, so the final bread is super tasty and flavorfully packed. We then fill the inside of the sandwich with a well-known combination of flavors to produce a really good sandwich fairly quickly.

Slideshow of the onion tart build process.

This is the underside of the first pizza dough onion tarts that I made. This thing is very tasty if you like lightly caramelized onions and cheese. You could and should make these just for snacks.
I tossed some arugula in with olive oil and balsamic vinaigrette and then paired that with prosciutto and cantaloupe for something really tasty.

Once you have this fancy-ass pizza dough with balsamic onions and cheese on the bottom you can just eat them. OR you can turn them into sandwiches which is what I did. I brought seasoned arugula, prosciutto, and canteloupe to the mix for a sandwich that ended up blowing my taste buds away.

The cheese creates a good crunchy crust on the pizza dough which lends texture to the sandwich.
Prosciutto and cantaloupe are a great pairing. Pizza dough and arugula make the whole sandwich come together.
Not the prettiest sandwich but it was so good.

Here’s the recipe for my dinner sandwich. You can have it for lunch as well. Or you can go nuts and eat it for brunch too!

40 minutes
French onion tart sandwich with prosciutto, melon, and arugula

The classic combination of melon and prosciutto is the focus here, but the quick bread made from store-bought pizza dough baked on top of onions and cheese turns this unique sandwich into something special.

Get Recipe


Biscuit dough sandwich

I made two versions of this cheesy biscuit and onion sandwich. The first was good but it was way too large. During the whole process, I learned that when you lay biscuit dough on top of a mound of onions and cheese, that dough will stretch itself and use gravity to reach downwards and outwards which stretches the dough in the oven to become wider as the baking process completes. I guess I could have assumed this was going to happen, but it took an attempt to figure it out.

Too big too meaty

This bad boy was big. I then was forced to overcompensate and use extra large sausage and potato patties to make sure that they were as wide as the biscuits. I must take photos of these things, after all. Making both patties larger was a good decision that also was actually bad. I used a 3.5-inch biscuit cutter to cut the original biscuits, but as I mentioned above, they spread out to be even wider.

Note: you can make these with store bought biscuit dough as well. They are typically less than 3.5-inches in diameter.

We can’t win them all and this was a very tasty loss. I still ate it though. But it was way too big to share as a recipe unless I was designing sandwich recipes for two.

Here’s the underside of a buttermilk biscuit with balsamic onion and cheese melted and caramelized on the bottom.
The girth is hard to tell from this photo, but believe me it’s big.
Don’t get me wrong, this was a good sandwich if you like breakfast sausage and caramelized onions but it was way too much for one sandwich for me.

Smaller and veggie-r

Here’s where the magic started to happen.

I really sized down my biscuit dough circle to get the optimum size for this sandwich. First, you want thin-ish dough. The biscuits will not be sliced, so you just need a thin biscuit dough that rises slightly in the beginning.

Second, you want a reasonably thin biscuit dough because when you lay it on top of a mound of things it will sag and start to reach out as the baking process works. I’ll be honest (as I said above) that I really didn’t think about this as a thing that could happen, but when you step back a bit it makes total sense. I ended up rolling my biscuit dough out to less than a half inch.

The plan for this sandwich is to use one thin biscuit as the top and one thin biscuit as the bottom sandwiching all ingredients. This way your caramelized onions and cheese end up in the middle with the other sandwich ingredients.

I ended up using the 3-inch biscuit cutter to start the biscuit sizes. Then the other ingredients don’t need to be as large.

Once you get the right dough size and shape, this is a super easy way to add extra flavor and cheesy goodness into a biscuit.

These biscuits are super tasty and almost steal the show in this sandwich. Just like the pizza dough above, you could just eat these biscuits as a side for bacon and eggs and they would be great.
The edges of the cheese start turning a bit brown, and they get a little crunchy which adds a bit of texture to the final sandwich.

For the rest of our biscuit sandwich, I skipped the sausage and chose to go with sliced avocado, a crispy patty made from mashed tater tots, and a simple folded egg.

I’ve written about turning tater tots into a crispy patty for a sandwich before. It works well. OR you could just buy the frozen, oval-shaped hash brown patties. But this way is more fun!
This was a much more manageable-sized sandwich and these three ingredients plus the crispy and melty cheese biscuit work well together.
You can see what I mean about how the biscuit dough sort of sags and conforms to the pile of onions and cheese by the way it angles out at the bottom (look at the top of the sandwich above). This doesn’t effect the final sandwich but it does mean your biscuit will be larger than the diameter that you originally cut.

Here’s my recipe for these vegetarian biscuit sandwiches with crispy cheese and onions. I think it’s fun for a slightly different breakfast option and I will be trying it again soon with different combinations of cheese, onions, and ingredients.

1 hour and 20 minutes
Cheesy onion biscuit with avocado, crispy potato, and egg

Here's a meatless breakfast sandwich (with egg and cheese) that you can make from scratch with flavors and textures that will excite even the meat eaters in the bunch. The biscuits are baked on top of cheesy balsamic onions which makes for a very exciting sandwich.

Get Recipe


Cheesy hot dog croissant-wich

This version of my trending tartwiches is the only one of the three where you only need to use one piece of dough per handheld. This version combines store-bought croissant dough and hot dogs into a cheesy oven-baked sandwich.

The hot dog, onion, and cheese bake at 400 degrees F (205 C), and then after 10 minutes you can add croissant dough. This gives the cheese and onions a bit of a head start since the croissant dough cooks very quickly. After adding the dough, bake for another 10 to 15 minutes or until the bread is nice and golden brown and the edges of the cheese are browning a little.

These “butterflied” hot dogs are sitting on top of shredded cheese, diced onions and mustard. Everything melts together in the oven.
You need to let these cheesy hot dogs cool slightly before removing them from the parchment.

Allowing the croissant-covered hot dogs to cool for a couple of minutes on the parchment helps the cheese to firm up a little bit so that it’s not quite as gooey. If you try to spatula them off the parchment immediately after bringing them out of the oven, you will make a bit of a mess.

This is one of the first batches of this sandwich that I made, and I didn’t give the cheese and hot dog extra time in the oven. Note there’s no real cheese browning or crisping. This is how I learned it needs an additional 10 minutes in the oven.
If you make too many of these cheesy croissant hot dogs, you can allow them to cool, refrigerate and then later reheat at 350 F for 7 to 10 minutes and they’ll be almost like fresh baked.

Building a cheesy Chicago dog croissant-wich

Here’s a simple 6 part process to adding the Chicago dog toppings on there. Remember, the mustard and onion are already baked into that layer of cheese blanketing the dog. Don’t try to yell at me that I forgot them!

Here’s the sliced hot dog laying under a bed of cheese, diced onion, and mustard.
Add two of the reddest tomato slices you can find in June. Normally I’d say salt the tomato, but salt is coming soon.
Lay down a slice of dill pickle.
Top with two or three sport peppers.
A couple of small spoons of the most neon green relish your store sells.
And then the most important ingredient is a little sprinkle of celery salt.

You don’t have to drag your cheesy croissant dog through the garden like I did. You can top it with whatever you want. It already has cheese, mustard, and onions in the mix, so add some chili and slaw or even something like pickled jalapenos and crispy onion strings and you’ve got yourself a great, cheesy croissant hot dog experience.

That crispy cheese wing on top is waving at you.
Hello, nice to cheese you!
Cheesy Chicago hot dog croissant-wich view printable page for this recipe

What do you get when you cross a Chicago-style hot dog with a cheesy croissant? Something awesome, that's what.


Cheesy croissant hot dog
  • 2 teaspoons vegetable oil
  • 14 onion, diced
  • pinch of salt and pepper
  • 14 cup cheddar jack cheese, shredded
  • 2 tablespoons yellow mustard
  • 2 hot dogs, sliced in half
  • croissant dough (store bought)
  • 1 whole egg
  • 1 tablespoon water
  • poppy seeds (optional)
Chicago dog assembly
  • 4 tomato slices
  • 2 dill pickle spears
  • 4 to 6 sport peppers (or pickled jalapenos)
  • 2 tablespoons pickle relish
  • celery salt


Cheesy croissant hot dog: preheat oven to 450 F (205 C).

Add 1 teaspoon of vegetable oil to a parchment-lined sheet pan. Top the oil with 2 tablespoons diced onion and a pinch of salt, and pepper. 

Pile half of the shredded cheese on top of the onions and then squirt 1 tablespoon of mustard on top of the cheese.

Top everything with one of the sliced hot dogs.

REPEAT for your second hot dog.

Bake at 450 F (205 C) for 10 minutes until the cheese starts to get very melty.

Cut croissant dough to the correct size to cover your split hot dog. For me, that was about a 3 x 5-inch rectangle.

Whisk 1 whole egg with 1 tablespoon of water. This is your egg wash.

Top each sliced hot dog with a piece of croissant dough and then with a brush or spoon, paint the top of the dough with egg wash. Add poppy seeds or salt and pepper to season the dough if using.

Once both pieces of dough are in place and painted with egg wash, place the pan back into the oven and bake for an additional 10 to 15 minutes until the dough is golden brown and the cheese is starting to brown around the edges.

When they are done, carefully remove each hot dog to a rack or plate to cool. At this point you can top with whatever you want. But I chose to go Chicago-style.

Chicago dog assembly: Carefully remove the cheesy croissant dog from the parchment and flip it over so that the cheese is facing up.

Add tomato slices, one dill pickle spear, and 2 to 3 sport peppers to the top of each cheesy dog. Spoon a little relish on top and sprinkle the whole thing lightly with celery salt.

Serve and enjoy.

I’ll take two cheesy Chicago hot dog croissant-wiches to go!

Hey you, come back next week

I think I’ll be making some more non-traditional wiches! You’ll just have to guess which kind!

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