|Source: Nancy Fogle (2003)|
|Prep time: 20 minutes||Cooking time: 45 minutes||Total time: 1 1⁄12 hours|
Preheat oven to 350°. Melt butter or margarine in a large skillet and sauté onions until tender. Add sour cream and mix thoroughly. Scoop half of onion mixture into a greased casserole dish. Top with 1/4 cup Parmesan cheese. Layer remaining onion mixture on top and sprinkle with remaining Parmesan cheese. Top with crushed Ritz crackers. Bake for 30 minutes.