For an extra layer of flavor, consider adding chopped walnuts, pecans, or chocolate chips to the batter before baking. If you don't have whole wheat flour on hand, you can substitute with all-purpose flour. However, whole wheat flour adds a delightful nutty flavor and slightly denser texture. Ensure your baking soda and baking powder are fresh for optimal leavening. Old leavening agents can result in a flat, dense bread. The bread is even more delicious the next day, as the flavors have had time to meld together. Store in an airtight container at room temperature for up to 3 days, or in the refrigerator for up to a week.