Combine first five ingredients -- flour, bran, baking soda, baking powder and salt.
Add pie spice if using.
Add vegetable oil, egg, banana, vanilla, yogurt and sugar. Stir until just combined.
Grease a 12-cup muffin tin. Spoon batter into tin. Bake for 22 minutes.
This recipe has several alternatives.
Cherry-Gingerbread. Omit pie spice. Add 1/2 cup chopped dried cherries, 1/3 cup molasses, 1 teaspoon cinnamon, 1 teaspoon ground ginger, and 1/4 teaspoon ground allspice. 180 calories per muffin.
Figgy Walnut. Omit pie spice. Add 3/4 cup sliced dried figs, 1/2 cup coarsely chopped walnuts and 1 teaspoon cinnamon. 187 calories per muffin.
Cranberry, Orange and Pistachio. Omit pie spice. Add 1/2 cup dried cherries, 1/2 cup chopped unsalted pistachios, 1 1/2 teaspoon grated orange rind, and 1/2 cup fresh orange juice. 179 calories per muffin.