Cut squash into chunks and chop onion. Add butter to sauce pan and add the squash, onion, garlic salt, and lemon pepper. Cook for about 20-25 mins on med high heat till the squash and onions are about tender. Remove from heat and crumble the crackers on top, add the slice of cheese and cover till cheese is melted. Stir well and add milk. You can either serve as is, or put in blender to make it creamed.