Another $5ish Family Meal--Creamy tuna casserole

I used to think tuna casserole had to have cream of mushroom soup in it.  Then I discovered that Campbell's Cream of Mushroom soup has MSG and autolyzed yeast extract (another form of MSG!) in it, which is not something I want to feed my family!  With this knowledge in hand, I started to make my tuna casseroles with Imagine Organic Creamy Portabello Mushroom Soup, but it is so expensive, I didn't want to use it often.  Then, I came across a recipe that didn't use any soup as a base, instead used a base of sour cream and milk.  Since I buy sour cream in bulk (5 lb container for about $5) from a restaurant supply store, this was a far more acceptable option.  The original recipe had a bunch of stuff I didn't like in it, so of course I tinkered with it, but here is the end result.

Creamy Tuna Casserole

12 oz uncooked pasta of your choice

10-12 oz canned tuna, drained

2 cups frozen peas

1 onion, diced

1 1/2 cups sour cream

3/4 cup milk

salt and pepper to taste

1/4 cup dry Italian bread crumbs

1/4 cup grated Parmesan cheese

2 tbsp butter, melted

Heat oven to 350 degrees.  Cook pasta according to package directions.  Combine pasta, tuna, peas, onion, sour cream, milk, salt and pepper in a 2 quart casserole dish.  Combine bread crumbs, cheese, and butter and sprinkle over the tuna mixture.  Bake uncovered 35 to 40 minutes or until hot and bubbly.