Russian Pork Roast

Preheat oven to 425 degrees F (220 degrees C).Preheat oven to 350 degrees F (175 degrees C).

Cut pork into 1/4-inch slices lengthwise, stopping 1/2-inch from the bottom, so it can fan out like a book. Stuff tomatoes, onion, and Gouda cheese in between the slices.

Combine garlic and salt in a bowl, then stir in mustard and pepper. Spread mixture all over the pork. Press pork slices firmly together and wrap in aluminum foil.

Bake in the preheated oven for about 1 hour 30 minutes. Uncover and continue baking until nicely browned, about 30 minutes more.