Ingredients

• 1/2 cup butter, 1 stick, softened
• 1/2 cup brown sugar, packed
• 1/2 cup granulated sugar
• 2 large eggs
• 2 teaspoons vanilla extract
• 1 cup mashed ripe banana, 9 ounces*, about 2 and 1/2 medium bananas
• 1 cup all-purpose flour, spooned and leveled
• 1/2 cup old fashioned oats, blended into a powder**
• 1 teaspoon baking soda
• 1 & 1/2 teaspoons baking powder
• 3/4 teaspoon kosher salt
• 1/2 cup sour cream
• 1/4 teaspoon cinnamon, optional
• 1/8 teaspoon nutmeg, optional
• 1/8 teaspoon cloves, optional
• 1/2 to 3/4 cup toasted pecans or walnuts, optional

Instructions

1. Prepare the pan and oven.
   Preheat your oven to 350°F. Coat a 9×5-inch loaf pan with nonstick spray or line it with parchment paper for easy removal.
2. Toast nuts (if using).
   Spread 1/2 to 3/4 cup chopped walnuts or pecans on a dry baking sheet. Toast at 350°F for 5–7 minutes, stirring every 2 minutes, until fragrant. Let cool completely.
3. Cream butter and sugars.
   In a large mixing bowl or stand mixer, beat the softened butter until smooth. Add the brown sugar and granulated sugar. Beat for about 2 minutes, until light and fluffy, scraping down the sides and bottom as needed.
4. Add eggs and vanilla.
   Mix in the eggs and vanilla extract until fully incorporated.
5. Mash and add bananas.
   In a separate bowl, mash about 2 1/2 very ripe bananas until mostly smooth (about 1 cup). Stir the mashed banana into the butter mixture.
6. Incorporate dry ingredients.
   Add the flour to the bowl but do not stir yet. Blend the oats in a blender or food processor until powdered (slightly gritty is fine), then add to the bowl. Sprinkle the baking soda, baking powder, and salt over the flour and stir them lightly into the flour to distribute evenly. Add optional cinnamon, nutmeg, and cloves if desired.
7. Combine wet and dry.
   Mix everything together just until combined, scraping the bowl to ensure no dry streaks remain.
8. Fold in sour cream.
   Gently fold in the sour cream until fully incorporated. If adding nuts, fold them in now.
9. Fill the pan.
   Transfer the batter to the prepared loaf pan and smooth the top.
10. Bake.
    Bake at 350°F for 55–65 minutes. Ovens vary, so begin checking near the end. Insert a toothpick deep into the center (aim for the crack on top). It should come out free of wet batter—moist crumbs are fine. The top should be golden brown and the loaf should pull slightly from the sides of the pan.
11. Cool.
    Let the bread cool in the pan for at least 20 minutes, then transfer to a cooling rack to cool completely before slicing.

• You may use up to 2 cups (18 ounces) mashed banana without adjusting any other ingredients. The loaf will bake successfully but will have a denser texture.
• If preferred, substitute the 1/2 cup powdered oats with 1/2 cup all-purpose flour.