6 mild Italian sausage links, casings removed
1 onion, chopped
1 green pepper, chopped
28 oz canned diced tomatoes
10 oz frozen green peas, thawed
2 tbsp canned tomato paste
1 tsp dried oregano
1 tsp dried basil
1/2 tsp dried thyme
1/2 tsp fennel seed
1/2 tsp salt, or to taste
1/2 tsp pepper
12 oz uncooked penne pasta, cooked according to package instructions
6 oz shredded part-skim mozzarella cheese