This recipe enhances a boxed brownie mix by incorporating sour cream and egg whites for a chewier, fudgier texture. Roasted nuts and dark chocolate chips are folded in, resulting in rich, moist, and decadent brownies perfect for a quick dessert or snack.
For truly chewy brownies, avoid overmixing the batter once the dry ingredients are added; mix just until combined. Overmixing develops gluten, leading to a cakey texture. Ensure you do not overbake; fudgy brownies are often slightly underbaked in the center when removed from the oven, as they continue to cook from residual heat. The sour cream is an excellent addition for moisture and richness; ensure it's at room temperature for smoother incorporation. Consider gently toasting the nuts if they aren't already roasted, which deepens their flavor. Allow the brownies to cool completely before cutting for clean slices and the best texture.