Ingredients
Method
- Preheat oven to 350°F (175°C). Foil-line 8x8 pan; lightly spray.
- Whisk melted butter, egg, yolk, brown sugar, vanilla, and sour cream smooth in bowl.
- Stir in brownie mix and salt just until combined into thick batter.
- Fold in white chocolate chips, reserving a few for top.
- Spread batter in pan; smooth top and sprinkle reserved chips.
- Bake 22–28 minutes until edges set and center jiggles slightly.
- Cool fully in pan before slicing neat bars.
