Tomato and onion jam: in a medium pot over medium heat, add all of your diced tomatoes and sprinkle the salt and celery salt over them. Stir occasionally while the tomatoes cook for about 5 minutes.
After 5 minutes, the tomatoes should be releasing some of their liquid, and you can add the brown sugar, onion powder, black pepper, and balsamic vinegar. Stir everything to combine and cook for about 20 minutes, stirring occasionally.
After about 20 minutes, everything should be getting closer to a jam-like consistency. If you would like it to thicken up more at this point, you can cook for another few minutes, but keep an eye on it and watch the consistency.
Once the texture of the tomato jam is where you'd prefer, add all of your diced onion and remove the pot from the heat. Stir to combine the onions fully.
Remove all of your jam into a sealed container and you can store it in the fridge for up to a week.
Calabrian chili mayo: in a medium bowl, add mayonnaise and Calabrian chilis and whisk to combine. Taste and add a pinch of ground black pepper if desired.
Store in a sealed container in the refrigerator for up to 2 weeks.
Griddled zucchini and weenie: place a griddle or pan over medium-high heat. Preheat the pan for 5 minutes.
Slice a hot dog or cooked sausage from end to end, almost all the way through, and open it up like a book or butterfly. Place the hot dog, flat side down in the pan and cook for 3 to 4 minutes.
Cut a zucchini in half and slice 3 or 4 slices about 1/4-inch thick. Try to get slices that will form a full layer inside your bread. In a small bowl, add the olive oil and the zucchini and toss to coat the zucchini slices in olive oil and then season with a dusting of Cajun seasoning or just salt and pepper. Place the slices of zucchini in the pan or griddle with the hot dog and cook for about 2 minutes per side.
Once the zucchini is in the pan, flip the weenie and cook for an additional 4 minutes.
Remove both the hot dog and zucchini to a plate to rest while you build the sandwich. Wipe out the pan and remove it from the heat if you plan to use it for panini.
Sandwich assembly: spread some Calabrian chili mayonnaise on the bottom slice of the roll. Top with half of the shredded cheese.
Layer the zucchini slices and then top them with the hot dogs/sausages. Spread on some tomato jam and then add the second portion of the cheese. Top with the top of the bread roll.
Panini: butter both sides of the sandwich and cook it in a panini press until the bread gets crusty and browned. If you do not have a panini press, you can use a hot cast-iron skillet with another skillet on top of the sandwich, pressing it down. This will grill the bottom side, and you will have to flip the sandwich, but it will work just fine.
Once both sides of the bread are browned and the cheese is melty, serve and enjoy.