Season pork with salt and pepper on all sides. Add marinade ingredients to a ziplock bag or a bowl. Add pork and massage meat in marinade to coat. Marinate for at least 1 hour, or up to one day. Remove from fridge 30 minutes before cooking to allow to come to room temperature.
On a grill, in a grill pan or in a skillet over medium high heat, cook pork loin for 7-10 minutes on each side, rotating slowly, until internal temperature reaches 145 degrees F. Remove to a plate, cover and allow to rest for 10 minutes before slicing thinly for sandwiches.
Slice Cuban bread roll or artisan baguette in half horizontally. Lightly butter the ousides of the bread. Spread mustard on each inside slice of bread. Layer a slice of cheese, pickles, ham, salt and pepper, pork, then cheese again. Sandwich with top piece of bread.
Cook sandwich in a hot panini press or in a hot skillet, pressing them down with a cast iron or heavy pan on top to toast them into a panini-style sandwich.
*Makes one giant sandwich that we cut into 8 portions/sandwiches.Bread: A traditional Cuban sandwich is made with a long, crusty loaf of Cuban bread (almost looks like the foot long bread from Subway, but with a crustier exterior). It can be difficult to find Cuban bread in some areas, so a loaf of French Bread, an artisan bread or Ciabatta would work, or try making Cuban Bread from scratch. La Brella brand sells a thin ciabatta loaf that’s similar to a Cuban roll and can be found in the bakery section of the grocery store.Make Ahead Instructions: All of the ingredients are fully cooked before you start assembling the sandwich, so all you really have to do is make sure the pork has marinated at least a day in advance before cooking. Refrigerate any leftovers and reheat without any additional pressing. They're good cold, too!Freezing Instructions: Let the sandwiches cool, wrap in parchment paper, then foil, and freeze. For extra protection, wrap in plastic over the foil. Rewarm in the oven (remove plastic warp) for a few minutes before enjoying.