Preheat the oven to 350° F. Generously grease a 9x5-inch loaf pan.
Sift the flour, sugar, baking powder, baking soda and salt into the bowl of an electric mixer. Add the cinnamon and allspice, and run the mixer briefly on low speed to blend the dry ingredients.
In a separate bowl, whisk together the eggs and the vegetable oil. Stir in the applesauce. With the mixer set a low speed, gradually pour the egg mixture into the dry ingredients. Add the sourdough and beat until thoroughly moistened. Stir in the walnuts. Pour into the prepared pan and bake for 50 to 60 minutes, covering the loaf with foil during the last 10 minutes if necessary to prevent overbrowning. Loaf is done when a wooden pick inserted in the center comes out clean.
Place pan on a cooling rack for 10 minutes, turn out and cool completely.
Servings: