Ingredients:

  • 2 cups All-Purpose Flour (spooned and leveled)
  • 1/2 cup Granulated Sugar
  • 1/2 cup Packed Light Brown Sugar
  • 1 tsp Baking Soda
  • 1 tsp Ground Cinnamon
  • 1/2 tsp Salt (Fine sea salt)
  • 1/2 cup Unsalted Butter, softened (room temperature)
  • 2 Large Eggs (room temperature)
  • 1 tsp Vanilla Extract
  • 1 1/2 cups Very Ripe Bananas, mashed (About 3-4 medium bananas)
  • 1/4 cup Sour Cream or Plain Yogurt
  • 1 cup Powdered Sugar (Sifted, for glaze)
  • 2 Tbsp Milk or Heavy Cream (for glaze)
  • 1/2 tsp Vanilla Extract (for glaze)

Instructions:

  1. Preheat oven to 350°F (175°C). Line a 9x13 inch baking pan with parchment paper, ensuring an overhang on the long sides for easy lifting. Lightly grease the exposed paper and pan sides.
  2. In a large bowl, cream the softened butter, granulated sugar, and brown sugar using an electric mixer until the mixture is light and fluffy (about 2–3 minutes).
  3. Add the eggs one at a time, mixing well after each addition. Mix in the vanilla extract, then gently fold in the mashed bananas and sour cream until just combined.
  4. In a separate medium bowl, whisk together the flour, baking soda, salt, and cinnamon until fully distributed.
  5. Gradually add the dry mixture to the wet mixture, mixing on low speed or by hand until the ingredients are just combined. Stop immediately when no dry streaks of flour remain; do not overmix the batter.
  6. Scrape the batter into the prepared pan and spread it evenly. Bake for 30–35 minutes, or until a toothpick inserted into the center comes out clean or with moist crumbs attached.
  7. Allow the bars to cool in the pan for 15 minutes. Use the parchment paper overhang to lift the entire slab onto a cooling rack and let it cool completely (about 45–60 minutes).
  8. If using the glaze, whisk together the powdered sugar, 2 Tbsp milk/cream, and 1/2 tsp vanilla until smooth. Add milk sparingly (1 tsp at a time) if the glaze is too thick. Drizzle or spread the glaze evenly over the cooled bars.
  9. Allow the glaze to set for about 10 minutes before slicing the slab into 12 uniform bars.