Combine orange juice, lime juice, minced garlic, and Cuban seasoning in a bowl to create mojo marinade.
Place pork tenderloin in marinade and refrigerate for 2-4 hours, turning occasionally.
Preheat oven to 400°F. Remove pork from marinade and roast for 25-30 minutes until internal temperature reaches 145°F.
Let pork rest for 10 minutes, then slice thinly against the grain.
Slice Cuban bread horizontally, keeping one side attached as a hinge.
Spread yellow mustard generously on the inside of both bread halves.
Layer ingredients in this order: roasted pork, ham, Swiss cheese, and pickle slices.
Close sandwich and butter the exterior of the bread generously.
Heat sandwich press or large skillet over medium heat. Place sandwich and press down firmly with press or heavy pan.
Cook for 3-4 minutes per side until bread is golden brown and cheese is completely melted.
Remove from heat, slice diagonally, and serve immediately.