Banana Blondies with Brown Sugar Frosting

These banana blondies are ultra-soft, buttery, and melt-in-your-mouth delicious. Made with ripe bananas, brown sugar, and optional brown butter, they’re topped with a silky brown sugar frosting that sets into a caramel-like layer. Easy enough for beginners but impressive enough for guests, these blondies are the perfect banana dessert.

Print Recipe Pin Recipe

Prep Time 20

Cook Time 30

Total Time 1 10

Servings: 12 bars

Course: Dessert

Cuisine: American

Calories: 230

Ingredients Equipment Method Notes

Ingredients

1/2 cup unsalted butter, melted or browned
1 cup packed light brown sugar
1 tsp vanilla extract
1/2 tsp kosher salt
1 large egg, room temperature
1 medium ripe banana, mashed
1 cup all-purpose flour
1/4 cup unsalted butter (for frosting)
1/4 cup packed light brown sugar (for frosting)
2 Tbsp milk
1 cup powdered sugar

Equipment

8×8 baking pan
Parchment Paper
Saucepan
Mixing Bowls
Whisk

Method

Preheat the oven to 350°F. Line an 8×8 baking dish with parchment paper and lightly spray with nonstick spray.
Melt butter in a saucepan. For brown butter, continue cooking until golden and nutty, then cool 5 minutes. Stir in brown sugar, vanilla, and salt. Add egg and mix until smooth. Fold in flour and mashed banana just until combined.
Spread batter into the prepared pan. Bake for 30 minutes, or until set and a toothpick comes out with moist crumbs. Cool completely.
In a saucepan, melt butter. Add brown sugar and milk. Bring to a gentle boil for 2–3 minutes, stirring constantly. Remove from heat and cool 5 minutes. Whisk in powdered sugar until smooth and spreadable.
Spread frosting over cooled blondies. Let set 15–20 minutes, then cut into 12 squares.

Notes

Do not overmix once the flour is added—this keeps the blondies tender. If frosting becomes too thick, whisk in a splash of milk; if too thin, let it cool longer.