Clean squash with water. Place in a large pot of salted boiling water. Cook for about 30 minutes until squash is tender when tested with a fork. Remove squash from water. Cut ends off squash. Place squash in a large bowl and mash with a potato masher. (Drain excess water from bowl)
Add cream cheese, 1 stick of butter and garlic salt to squash and a little salt and pepper (if desired) while squash is hot. Mix well. Place in a buttered 9 x 13 casserole dish (I use a vegetable spray).
Crush a sleeve of Ritz crackers and mix with the melted butter. Sprinkle on top of casserole. Cook for 30 minutes at 350 degrees.