Brown Butter Blondie with Speculoos Buttercream That’ll Ruin You for Regular Blondies Forever
Rich and chewy brown butter blondies topped with a fluffy Speculoos cookie butter frosting, perfect for dessert lovers.
Ingredients
- 1 cup butter plus 1 tablespoon butter, divided
- 2-1/4 cups packed brown sugar
- 3 large eggs, room temperature, lightly beaten
- 2 teaspoons vanilla extract
- 2-1/4 cups all-purpose flour
- 1-1/2 teaspoons baking powder
- 2-1/4 teaspoons ground cinnamon
- 1/2 teaspoon sea salt
- 1 cup chopped walnuts, toasted
COOKIE BUTTER FROSTING:
- 2/3 cup butter, softened
- 1/4 cup confectioners’ sugar
- 3/4 cup Biscoff creamy cookie spread
- 1 teaspoon vanilla extract
- 1/2 teaspoon ground cinnamon
- 1/4 teaspoon sea salt
Instructions
- Preheat oven to 350°F (175°C). Line a 13×9-inch baking pan with parchment, letting the ends extend up the sides. Grease parchment with 1 tablespoon butter and set aside.
- In a large bowl, mix together flour, baking powder, cinnamon, and salt. Set aside.
- In a small heavy saucepan, melt 1 cup butter over medium heat. Cook for 5-7 minutes until golden brown, stirring constantly. Remove from heat and add brown sugar and vanilla, stirring until smooth. Quickly stir in eggs until well combined.
- Add the wet mixture to the dry ingredients; stir until combined. Fold in walnuts.
- Spread batter into prepared pan and bake for 30-35 minutes, or until golden brown. Cool completely in the pan on a wire rack.
- For the frosting: In a large bowl, cream butter and confectioners’ sugar until smooth. Add cookie butter, vanilla, cinnamon, and salt. Beat until light and fluffy, about 3-4 minutes.
- Spread frosting over cooled blondies. Cut into bars and serve.
Notes
- Toast the walnuts beforehand for extra flavor and crunch.
- Make sure the blondies are completely cooled before adding the frosting to prevent melting.
- Store leftovers in an airtight container at room temperature for up to 3 days or refrigerate for longer freshness.