Preheat oven to 350. Lightly butter a 9 x 5 inch loaf pan. Line bottom and long sides of pan with parchment paper. Butter the top of the parchment. Dust pan with flour, tapping out excess. Using a fork, mash bananas in a bowl. You should have about 1 cup. In another bowl, sift together the flour, baking soda and salt. In a third bowl, using handheld mixer on high speed, beat together butter and sugar til light in color an texture, about 3 minutes. Gradually beat in eggs and then the mashed bananas. Reduce speed to low and add the flour mixture in 3 additions alternately with the sour cream in 2 additions, beginning and ending with flour mixture and stopping to scrape down bowl as needed. Beat til smooth. Fold in chocolate chips and half of the walnuts. Pour batter into prepared pan and smooth the top. Sprinkle remaining walnuts on top. Bake til toothpick inserted in center comes out clean, about 1 hour. Transfer to wire rack and let cool in pan for 5 minutes. Turn out onto rack and remove paper. Invert again and let cool completely. Cut into slices and serve warm or at room temperature.
Photo and recipe courtesy Breakfast Comforts