Pizza Casserole

Sick of making the same dishes every week?  Sick of ordering pizza when you can't think of anything else to have?  We all have weeks like that right?  I am constantly searching for new dinner ideas, and always trying to think of new things to throw together. 
As I've mentioned before, I have a soft spot for casseroles.  Don't know why, but I really love a one dish meal, especially during the week.  I came across a recipe a while ago for a little bit of a different version of a pizza casserole and realized right away that it was a great idea, and so easy to tweak to your personal preferences in terms of "toppings".  It was a hit in our house, and every time I've made it sense then I have changed it, depending on what kind of "pizza" I was in the mood for.  The possibilities are endless with this dish, so I'll give you a basic recipe to start you off with. 
Change it up and get creative.  There are no rules with this dish!

Pizza Casserole
1/2 a box of bow tie pasta, cooked until al dente and drained
1, 26 oz jar spaghetti sauce (use homemade sauce if you have it)
1/2 of a large onion, chopped
2 tsp chopped garlic
1 tsp oregano
1/2 lb sweet Italian sausage
1/2 lb cooked ham, cut into cubes
1 container of sliced mushrooms, whatever kind you prefer (I use baby Portabella)
2, 8 oz bags shredded mozzarella
sliced pepperoni - amount to use is up to you
grated Parmesan cheese - amount to use is up to you
Crumble up the sausage in a medium sized pan, and add the onion,garlic and oregano.  Cook until the juices run clear.
Spray an 8 x 11 pan with cooking spray, and preheat the oven to 375.  Coat the bottom of the pan with a thin layer of sauce.  On top of the sauce add 1/3 of the pasta, 1/3 of the sauce, 1/3 of the shredded mozzarella, sprinkle a little of the Parmesan cheese on top of the mozzarella, add the sausage mixture, and then add 1/2 of the package of mushrooms.  For the next layer, add 1/2 of the remaining pasta, 1/2 of the remaining sauce, 1/2 of the remaining mozzarella, sprinkle on the Parmesan cheese, add the ham and the rest of the mushrooms.  For the final layer add the rest of the pasta, all of the remaining sauce, the rest of the mozzarella cheese, sprinkle on some Parmesan cheese and cover the top completely with a layer of pepperoni.
Place in oven and bake for 45 minutes.  Remove from oven and let it set for 5-10 minutes before serving.