This is a recipe that I have not yet set out to measure what all goes in it either. It is my own recipe and it changes a little each time. Penne pasta is my favorite for this dish, and I boil it as directed on the box, then drain, rinse and put in a large mixing bowl.
Meanwhile, I have already peeled about 2lbs of shrimp, chopped a large onion and an 8oz package of mushrooms. I have cleaned and prepared appx. 2 cups of broccoli florets. I use an 8oz package of fat free creme cheese, a 12oz bag of shredded mozzarella, grated parmesan (have no idea how much), some white wine (some goes in the cooking- some goes in the cook), water, 1 can of diced tomatoes rinsed, Tbsp or more of cornstarch, basil, minced garlic, oregano, salt and pepper, olive oil, and half a stick of margarine.
Start with the olive oil and margarine in a large skillet over medium heat. Add onions, mushrooms and garlic. When the onions are clear and start to "brown", add some wine and water to make rather wet. Add creme cheese, and spices bring to a slow boil. Stirring constantly to melt down the creme cheese. Add shrimp, about 3 tsps of grated parmesan (more sometimes) and keep stirring.
When the shrimp turn pink after a couple of minutes add the cornstarch mixture* (*-I put my cornstarch in a small juice glass then add white wine to cover the starch and stir to mix.) Turn heat up to medium high and continue to stir constantly. Add broccoli and keep stirring. As the mixture begins to thicken remove from heat.
Now put this mix over the top of the pasta in the large mixing bowl and combine.
Spray a casserole dish, or aluminum pan with non-stick spray. Transfer the mix to the pan and cover with the mozzarella cheese.
Place in a preheated oven at 350 degrees for 30 minutes. I like to turn the broiler on for the last couple moments to brown the top, but don't leave it at this point - it will burn.
Serve with garlic bread and a salad!