Preheat oven to 350.

Thinly slice squash and onions, and saute in large pot with butter and olive oil until tender.

Butter an 8x8 casserole dish.

Shred cheese and place in mixing bowl

Add soup and egg, and mix.

Add squash mixture, and mix.

Pour into casserole dish, and place in oven for 45-60 minutes, or until it is just beginning to brown on top.

Crush crackers and sprinkle them over the casserole.

Place back in oven for 15-20 minutes or until crackers are browned.

Serve and enjoy.