1 can (14 1/2-oz) diced tomatoes, undrained
1 can (6-oz) tomato paste
2 green bell peppers, chopped
1 pkg (8-oz) sliced fresh mushrooms
1 small onion, chopped
1 lb pork tenderloin
1 tsp oregano
2 cups whole-grain penne, raw
1 tbsp cornstarch
1/4 cup water
1 cup shredded mozzarella cheese
2 tbsp grated Parmesan cheese
Pour the tomatoes and tomato paste into a slow cooker or crockpot; stir together to blend well. Stir in the bell peppers, mushrooms, and onion.
Cut the pork into 8 to 10 pieces approximately 1/2-inch thick. Sprinkle the oregano over the meat; place into the cooker. Using the back of a large spoon, press the meat into the tomato mixture. Place the lid on the cooker and cook on low 4 to 5 hours or on high 2 1/2 to 3 hours.
Cook the penne according to the package directions, omitting salt called for.
Transfer the meat to a plate leaving the sauce in the cooker. Cover meat with foil to keep warm.
Mix the cornstarch and water together until smooth; add to the sauce and stir. Cover and cook another 6 to 8 minutes until thickened.
Drain the penne and spoon into serving bowls. Top with the meat, sauce, and cheeses.