Make Cake

• Preheat the oven to 350 ℉ and grease a bundt pan. In a small bowl, combine the 2 tablespoons brown sugar and 2 teaspoons cinnamon; set aside.
• In a large bowl, using an electric mixer, cream the ½ cup unsalted butter and 1 cup granulated sugar on medium speed for about 2 minutes. Beat in the 2 large eggs one at a time, then mix in the 1 ½ cups mashed bananas, ¾ cup sour cream or plain yogurt, and 1 teaspoon pure vanilla extract.
• In a medium bowl, whisk together the 2 ⅓ cups gluten free flour or oat flour, 1 teaspoon baking powder, 1 teaspoon baking soda, and ½ teaspoon fine sea salt. Beat the dry mixture into the wet mixture on low speed until combined.
• Pour half of the batter into the prepared pan, then sprinkle the cinnamon-sugar mixture evenly over it. Top it with the remaining batter and smooth the top. Rest the batter for 15 minutes, then place it in the oven and bake for 45-50 minutes, until a toothpick inserted in the center comes out clean. Remove pan from oven, place on a rack, and let cool in the pan for 10 minutes before gently turning out onto the rack to cool fully.