Banana Walnut Coffee Cake
Preheat the oven to 350 degrees. Butter a 10-inch tube pan; dust with flour, tapping out the excess, and set aside.
To make the walnut and sugar sprinkle, combine the walnuts, sugar, and cinnamon in a small bowl and set aside.
In a large bowl, cream the butter with an electric mixer on high speed until it is light. Gradually beat in the sugar and continue beating until light and fluffy. Change the mixer speed to medium. Beat in the eggs, one at a time, beating well after each addition, then beat in the sour cream, mashed bananas, and the vanilla.
Bake until a skewer inserted halfway between the sides and the tube of the pan comes out clean, about 1 hour and 15 minutes. Let cool in the pan on a wire rack for 20 minutes. Carefully loosen the cake from the sides and tube of the pan, then invert onto a wire rack and turn right-side-up. Serve warm or cool, sprinkled with sifted confectioners' sugar, if desired.
This recipe yields one 10-inch tube cake.
Comments: Bananas add both sweetness and moisture to coffee cakes. Overripe bananas that are too soft for eating are ideal for this recipe.