Combine mayonnaise, onion, 1/4 cup cracker crumbs, egg, sugar, salt, and pepper. Add mashed squash; mix well. Pour squash mixture into a lightly greased 1-quart casserole.
Sprinkle remaining cracker crumbs over squash mixture. Bake, uncovered, at 350° for 25 to 30 minutes; sprinkle cheese on top. Bake an additional 5 minutes or until cheese melts.
Oxmoor House Homestyle Recipes
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