tomato and cheese casserole

4 onions, sliced thin
3 T butter
-6 large garden fresh tomatoes, sliced thick
1 c grated chedder
1/2 c grated jack cheese
1 c bread crumbs
salt and pepper
paprika
2 eggs, beaten
1 cup sour cream
In a skillet saute onions in butter.Grease a 2 qt casserole and layer w/ tomatoes on bottom. then layer of cheese,(mixed), bread crumbs and then onion. salt and pepper and repeat ending with tomatoes on top. In a small bowl mix the eggs and sour cream til smooth and pour over casserole. Paprika and salt and pepper. Bake covered 375 oven 30 min. uncover and cook another 15 min. til brown and bubbly.