Slice the bananas into 1/2 inch slices. Place slices into a freezer bag or airtight container and put in the freezer for 3 hours or until frozen. With a hand blender, blend the bananas together. It might take some elbow grease, but they will lighten in color and look creamy once blended. Mix in any flavorings desired and replace the mixture in the freezer in an airtight container and freeze for at least one hour. Top with seasonal fruit and/or nuts (we used blueberries and walnuts)!