Marinate pork chops: depending on the thickness of your piece of pork, it might be best to butterfly it to make it sized a bit better for a sandwich. The photo below is not a pork chop, but it is meant to illustrate that butterflying meat is the act of cutting it almost fully in half to open it up like a book leaving you with a wider and thinner piece of meat. 

Once you have done that, place the pork in between two pieces of plastic wrap or in between a plastic zip-top bag and pound the pork to flatten it more and make it a bit larger. 

Add the flattened pork chop to a bowl or plastic zip-top bag with 1/2 cup buttermilk, 1/2 teaspoon salt, and 1/2 teaspoon ground black pepper. Let the pork marinate for at least one hour and up to overnight. 

Spinach and peppers: add a tablespoon of olive oil to a large pan over medium heat. When the oil starts to shimmer, add the spinach a handful at a time. It might look like you have too much spinach for the size of your pan, but it will shrink a lot. 

As the spinach cooks, keep adding handfuls until all of the spinach is in the pan. Cook for 2 to 3 minutes, stirring the spinach around until it has all wilted, shrunk, and softened. Season the spinach with 1/4 teaspoon of salt and 1/4 teaspoon of pepper. 

Move the spinach to the side of the pan and then add the minced garlic directly to the pan. Cook the garlic for 2 minutes and then stir it all together with the spinach.

Add the finely chopped red pepper and cook with the spinach for another 3 or 4 minutes. Taste the spinach now to see if it needs more salt and pepper. 

After everything has cooked together move all of the spinach and peppers to a bowl or container to rest. You can put the spinach in the refrigerator if you're not making a sandwich immediately and rewarm it in the microwave or in a small pan when it's time to build the sandwich. 

Cook pork chops: when it's time to sandwich remove the pork chops from the marinade and try to remove as much of the buttermilk as you can. Dry the pork chops off before cooking because if the meat is wet it will not brown in the pan. 

Add a tablespoon of butter and a tablespoon of olive oil to a medium pan over medium heat. While the butter is melting, add just a pinch of salt and black pepper to both sides of the pork chops. 

When the butter is melted and bubbling add the pork chops and cook for 4 minutes on the first side and then flip and cook for an additional 2 to 3 minutes. 

After the pork has been cooked remove it to a plate or cutting board while you prepare the sauce. 

Creamy mustard sauce: after the meat has been removed from the pan, add chicken broth and then stir in the Dijon mustard.

Once the Dijon mustard is fully whisked in, add heavy cream and simmer the sauce for 3 to 5 minutes. The sauce should start to thicken. Taste it to see if it needs salt and black pepper. 

Once the sauce has thickened a little, turn off the heat and get ready to make the sandwich. 

Sandwich assembly: slice your bread rolls and spread or drizzle a little sauce on the bottom roll. 

Cover the sauce with the cooked pork and then layer on one or two slices of cheese. You do not have to melt the cheese, but this is the point where you can place the bottom of the sandwich under a broiler to melt the cheese. If you do not have a broiler you can heat your oven to 350 F and cook for 4 or 5 minutes to melt the cheese.

Top the cheese with spoonfuls of spinach and peppers and then drizzle on a bit more of the creamy mustard sauce on the top roll. Then close the sandwich and serve.