Italian Rigatoni and Spinach Chicken

3 c cooked chicken
1 onion
2 T olive oil
1 can Italian tomatoes
2 c dry pasta (I used elbow macaroni)
9 oz frozen spinach, thawed and pressed) - I only had fresh, so I used that
1 pkg Philly Cooking Creme onion and chive - I only had cream cheese, so I used it
1 t garlic powder and 1 t onion powder - I added this since I used the plain cream cheese
2 t salt, 1/2 t black pepper
2 c shredded mozzarella

The original recipe said to cook the chicken and onion separately, but I combined them, and cooked them in the oven in olive oil til the chicken was done, then cut everything into bite size pieces. Cook the pasta as directed, then drain. In a large bowl, stir together pasta and cream cheese. then add a can of drained tomatoes. If you do not have Italian style, you can add a t of Italian seasoning. Chop and stir in spinach. stir in rest of ingredients, except mozzarella. place in greased casserole, top with cheese. Cook for about 30-35 minutes at 350 degrees.