1Preheat oven to 350° (325° for dark or coated pan).
Spray a 9x13-inch cake pan with Baker's Joy, or grease and flour pan.
2With a mixer in a large mixing bowl, mash bananas. Add orange juice, buttermilk, and egg whites. Blend well. Add cake mix in 2 parts, beating well after each part. Beat for a total of 2 minutes at medium speed.
3Spread cake batter in prepared pan and bake 32-35 minutes (maybe 3-4 minutes longer if using dark pan at 325°). When done, cake will spring back when lightly touched. Cool cake in pan. Frost with your favorite frosting - we like cream cheese frosting. Sprinkle with chopped nuts.
4VARIATION: to make this with a plain yellow cake mix, omit the orange juice and increase the buttermilk to 1/2 cup. If desired, stir in 1 cup chocolate baking chips. Mix and bake as directed above. Frost with Chocolate Glaze for Bundt Cakes.