In a Thatsa ® bowl, cream the margarine and sugar; add eggs, mashed bananas, milk and vinegar. Stir well. Add dry ingredients and nuts (if desired). Pour into 2 buttered or sprayed loaf pans. Bake at 375 degrees for 45 minutes to 1 hour. Or by using mini loaf pans you can make 4 small loaves and bake at 375 degrees for 20-30 minutes. Cool on wire rack before removing.