Baked Ziti w/ Italian Sausage

I made this several years ago and just thought about making it again. It's easy and very good. Not exactly low-calorie, but hey- you gotta live sometime right?

This recipe is modified from Allrecipes.

INGREDIENTS
1 pound spicy Italian sausage, casings removed
1 diced onion
1 diced red bell pepper
2 (14.5 ounce) cans diced tomatoes, one drained, and one with liquid
3 (3 ounce) cans tomato sauce
1/4 teaspoon garlic powder
1 1/2 teaspoons salt
1 teaspoon dried oregano
1 pound dry ziti pasta
Handful of fresh mushrooms, coursely chopped
8 ounces shredded mozzarella cheese
1/4 cup grated Parmesan cheese

DIRECTIONS
1. In a skillet over medium heat, cook sausage with bell pepper and onion until sausage is evenly browned, about 5 to 10 minutes. Drain excess grease. Add tomatoes, tomato sauce, garlic powder, salt, and oregano. Simmer while preparing pasta.

3. Bring a large pot of lightly salted water to a boil. Cook pasta for 8 to 10 minutes, or until al dente; drain.

4. Preheat oven to 350 degrees F (175 degrees C). In a 3 quart baking dish, layer ziti and sauce mixture.

5. Bake for 40 minutes in the preheated oven. Remove and sprinkle top with cheeses. Return to the oven for five minutes.