Rustic Penne Pasta

This is one yummy dish!  We are not big on jarred sauce at our house; too sweet.  I am always looking  for recipes, though, that are kind of saucy with basic ingredients. I don't even remember where I found this recipe originally, but over the years, I have made additions and alterations that work for us.
One of the nice things about this recipe is that it is very flexible.  You could green peppers, or squash to incorporate more vegetables.  You can also use whatever pasta you like best (normally we really like penne, but I didn't have any when I made this particular meal, so it's campanelle). Finally, you can substitute the cheese.  The recipe calls for mozzarella, but I have used various italian mixes and blends and they always turn out good.
Side note, the pictures are not so good and don't do the meal justice.  One day, I will figure out how to photograph food. :/

Rustic Penne Pasta

1 lb ground beef or turkey

1/2 tsp butter

1 large onion, chopped

6oz button mushrooms, sliced

3 1/2 c penne pasta

1 can (14.5oz) diced tomatoes w/basil, garlic, and oregano

1 can (6oz) tomato paste

1/2 c water

3 c shredded mozzarella cheese, divided

Boil the noodles as directed and set aside. In a large skillet, melt the butter and saute the onions and mushrooms, set aside when done.  In the same pan, brown the meat and drain excess fat.  Add the onions and mushrooms, and the tomatoes, tomato paste and water to the meat and stir. Season with salt and pepper to taste (I don't typically add too much), and heat through allowing sauce to simmer. 

Combine the pasta with the meat sauce and mix. Add 2 cups of the cheese and mix in.  Pour into a baking dish and top evenly with remaining cheese.

Bake uncovered in a preheated oven at 350 degrees for 20-25 minutes, until cheese is melted and it's heated through. Serve with salad or a heated vegetable like green beans or broccoli (my sons favorite). Serves 6-8. Enjoy!