Instructions:

This Can't be Squash Casserole

Source: Footsie's own again, adapted from several different recipes

4 pounds yellow squash, cooked with salt,
    well drained, mashed
1/2 stick butter or margarine
1 medium onion, chopped
1 cup bread crumbs, (seasoned
    preferred, but not necessary)
1 can cream of mushroom soup
2/3 soup can milk
1/2 cup mayonnaise
2 eggs, beaten
1 cup Cheddar cheese
Salt and pepper to taste

Cook the onion in the butter just till tender. Combine all ingredients until well mixed. Spray 9 x 13-inch pan with nonstick spray, spread mixture evenly in pan. * (Can be covered and refrigerated several hours or overnight at this point.)

Bake uncovered, in 350 to 375 degrees F* oven until lightly browned on edges and bubbly, about 45 minutes to an hour.

* My oven knob has no numbers on it, so I rarely get the same temperature each time, which is why I guessed at it.