: Preheat oven to 325 degrees Fahrenheit. Line a muffin tin with paper liners and set aside.; In a large bowl, whisk together flours, baking powder, baking soda, and salt.; In a medium bowl, mix the sugar or honey, egg and egg whites, oil, and yogurt.; Add the wet ingredients to the dry ingredients, along with the zucchini and walnuts. Stir to combine.; Fill muffin tins about two-thirds full and bake 25–30 minutes, or until a toothpick inserted in the center comes out clean. Let cool on a rack.; Credits: