Whisk together orange juice, lime juice, olive oil, minced garlic, cumin, oregano, salt and pepper in a bowl. Place the pork shoulder in a shallow dish or zipper bag and pour the marinade over it, massaging to coat. Refrigerate for at least 2 hours and preferably overnight (up to 12 hours) for best flavor.

Roast pork

Preheat oven to 150°C (300°F). Remove pork from refrigerator and transfer to a roasting pan. Pour any remaining marinade over the pork. Roast uncovered for about 2 to 2.5 hours, or until the internal temperature reaches 90°C (195°F) and the pork is very tender and falling-apart. For a crisper exterior, increase oven to 230°C (450°F) for the last 10-15 minutes, watching carefully to avoid burning. Rest the pork for 15 minutes, then shred or slice thinly against the grain.

Alternatively

If using pre-cooked or store-bought roast pork, skip the marinating and roasting steps. Thinly slice or shred enough pork to equal the listed quantity and warm gently before assembling the sandwich.

Sandwich Assembly & Cooking

Prepare bread

Cut the loaf into sandwich-length portions (makes 2 generous sandwiches). Slice each portion lengthwise, keeping a hinge if you prefer, and hollow slightly to remove some crumb so fillings sit comfortably and the sandwich presses evenly.

Spread condiments

Spread about 1/2 tablespoon yellow mustard on the bottom half of each sandwich portion. Spread a thin layer of softened butter on the outside of both bread halves (the exterior face that will contact the grill) to promote browning and crisping.

Layer fillings

On the mustard-coated bottom half layer: 1) place half of the warmed roast pork in a thin, even layer, 2) top with the ham, 3) add Swiss cheese slices evenly over the ham, and 4) arrange dill pickle slices over the cheese. Close the sandwich with the top half of the bread, buttered side out.

Press and grill

Preheat a heavy skillet, griddle, or panini press over medium heat. If using a skillet or griddle, place a heavy oven-safe skillet or foil-wrapped brick on top of the sandwich to press it down. Place the sandwich (buttered side down) on the hot surface and press firmly. Cook 3-5 minutes until the bottom is golden brown and the cheese begins to melt. Flip, press again and cook another 3-4 minutes until the second side is golden and the cheese is fully melted. Adjust heat as needed to avoid burning while allowing cheese to melt.

Slice and serve

Remove the sandwich from the grill and transfer to a cutting board. Let rest 1 minute, then cut each sandwich in half diagonally. Serve hot so the cheese remains gooey and the bread is crisp.