Cook squash, covered, in a small amount of boiling water 8 to 10 minutes or until tender; drain well, pressing between paper towels.
Combine squash and butter in a bowl; mash until butter melts. Stir in eggs and next 7 ingredients; spoon into a lightly greased shallow 2-quart baking dish. Sprinkle with crushed crackers.
Bake at 325° for 30 minutes. Sprinkle with cheese; bake 5 more minutes or until cheese melts.
*2 1/2 pounds zucchini, sliced, may be substituted.