Zucchini Cheddar Puff
2. In a bowl combine sour cream, egg yolk, flour, onion, salt and pepper. Stir in cheese.
3. In a bowl beat egg whites until fluffy stiff peaks form. Fold into sour cream mixture. Spoon onto squash. Mix bread crumbs and butter together and sprinkle over dish.
4. Bake at 350 degrees for 20 to 25 minutes.