1crush saltines into a large bowl. cook bacon until crisp. Chop onions and add to bacon fat melt butter in same pan. Warm milk in sauce pan, add bacon, cooked onions, butter into crackers and mix well. add milk, stir until combined, mixture will be soupy. put into 9x13 pan or large casserole bake at 350 until browned on top and set, but not dry.