Gluten-free Banana-walnut Muffins

Directions

1. 1
   Preheat oven to 350 degrees. Line a 12-cup muffin tin with baking cups. Whisk together brown-rice flour, ground walnuts, potato starch, tapioca flour, baking powder, xanthan gum, and salt. Whisk together yolks, oil, sugar, bananas, and vanilla. Fold flour mixture into banana mixture.
2. 2
   Whisk whites until stiff peaks form. Working in 3 batches, fold whites into batter. Fill each baking cup with batter. Bake until light golden brown and a toothpick inserted into the centers comes out clean, 22 to 24 minutes. Let cool slightly. Turn out muffins onto a wire rack, and let cool completely.