Still not it, but getting closer. :) I don't see why you couldn't substitute grapefruit and add more banana slices.

ORANGE BANANA BREAD

3 or 4 Texas Oranges
2 ripe bananas
1 cup sugar
1/3 cup vegetable oil
2 eggs
1 teaspoon vanilla
1 cup whole wheat flour
3/4 cup all-purpose flour
1/2 cup wheat germ
1 teaspoon baking soda
1/4 teaspoon salt
1/2 cup chopped pecans

Preheat oven to 350 degrees F. Grease a 9x5x3-inch loaf pan well.

Grate 1 tablespoon peel from oranges and set aside. Peel and section oranges to equal 1 cup sections. Drain well.

Combine orange sections, bananas, sugar, oil, eggs, vanilla in the container of an electric blender; blend until smooth.

Combine grated peel and remaining ingredients in a mixing bowl. Pour orange mixture over dry ingredients. Mix gently with a spoon until all ingredients are moistened. Pour into prepared loaf pan.

Bake at 350 degrees F for about 1 hour or until done. Cool on a wire rack.

Yield: 1 loaf
Source: TexasSweet Citrus Marketing