The Best Cuban Sandwich

Name: The Best Cuban Sandwich
Prep time: 25 min
Cook time: 3 h
Total time: 3 h 25 min
Cuisine: Latin American, Cuban, American
Ingredients: 4 Cuban Bread; 3 tbsp butter; 1 lb Cuban Roast Pork; 8 slices sliced ham ((sweet cured or smoked, Serrano, or bolo ham - I used honey ham); 8 slices Swiss Cheese; Dill pickle slices; Mustard (optional I used a Dijon but a spicy brown would be great or just yellow too.); *Sriracha (Optional); 4 pound Pork shoulder roast ((also known as a pork butt)); 1 garlic clove; 1 tsp salt; 1 tsp black peppercorns; 1 cup sour orange juice (I used 2/3 cup 100% orange juice (not from concentrate, 1 lime juiced and 1 lemon juiced)); 1 cup minced onion; 2 tsp dried oregano; 1/2 cup olive oil (Spanish if you have it. I used Italian)