Preheat oven to 450 degrees F.

Combine salt, pepper, and 1/4 cup of Chinese mustard in a small bowl.

Spread mixture on all sides of the pork loin roast.

Place pork loin roast, fat side up, in a shallow roasting pan.

Roast for 15 minutes.

Reduce oven temperature to 350 degrees F.

Continue roasting for 40-45 minutes, or until the internal temperature reaches 145-160 degrees F.

Remove pork loin roast from oven and let rest for 10 minutes.

Slice pork loin roast very thinly.

Halve the submarine rolls.

Butter the outside of each roll half.

Spread remaining Chinese mustard (1 1/2 tablespoons) on half of the roll halves.

Spread red plum jam (1 1/2 tablespoons) on the other half of the roll halves.

Arrange honey ham, roast pork, Swiss cheese, and green chiles on the mustard halves of each sandwich.

Top with the jam halves.

Prepare a grill to medium-hot heat.

Lay a double layer of foil on the grill.

Place sandwiches on the foil.

Place bricks over the sandwiches (2 sandwiches per brick) and press down gently.

Grill until the bottom of the bread is browned and the cheese starts to melt (2-3 minutes).

Turn sandwiches, replace the bricks, and grill for 2 minutes more.

Cut sandwiches in half and serve.