1 ½ cups white whole-wheat flour 1 teaspoon baking powder 1 teaspoon ground cinnamon ¾ teaspoon baking soda ½ teaspoon salt ⅓ cup plain whole-milk Greek yogurt ⅓ cup creamy natural peanut butter, well stirred 2 large eggs 1 cup mashed banana (from 2 very ripe bananas) ½ cup packed light brown sugar ⅓ cup granulated sugar 1 teaspoon vanilla extract ¾ cup chopped walnuts, toasted
Preheat oven to 350°F. Line a 12-cup muffin tin with paper liners.
Whisk flour, baking powder, cinnamon, baking soda and salt together in a medium bowl. Set aside.
Whisk yogurt and peanut butter together in a large bowl until smooth.
Add eggs, banana, brown sugar, granulated sugar and vanilla; whisk to combine. Fold the flour mixture into the banana mixture until the flour is mostly incorporated.
Bake until a wooden pick inserted in the centers comes out clean, 18 to 22 minutes.
Remove from oven; let cool for 5 minutes. Serve warm or let cool completely, about 30 minutes.