These Chewy Black and White Blondies are bar cookies that have swirls of both chocolate and vanilla, making them a crowd pleasing favorite that the whole family will enjoy! The recipe is simple to make, which is one of the things that I love about it. It starts with just one vanilla batter, which is divided and has chocolate added to a portion. There is plenty of chocolate to make the brownie portion of the batter rich enough to satisfy any chocolate lover, while still being perfectly balanced with the vanilla.
The brownies are chewy and lean towards being slightly cakey, rather than the dense and fudgy texture that is common in most brownie recipes. This is in part because the blondies have an unusual ingredient in the batter: mayonnaise! Mayo is not a common ingredient in blondies or brownies, but there are quite a few cake recipes out there that include it. A basic mayonnaise is made with oil and egg yolks, so it adds plenty of fat to a recipe. That extra fat adds moisture and increases the tenderness of the finished baked good. In the case of this recipe, the brownies are slightly cakey and very chewy without being dry. It’s a deliciously addictive texture for a bar cookie to have!
The blondies will be ready to eat once they have cooled to room temperature, but I find that they are even better the day after they have baked. After being store in an airtight container overnight, the vanilla and chocolate flavors of the blondies really come out and deliver even more impact than they have when they’re freshly baked. Dress them up with a drizzle of chocolate ganache or a smear of vanilla frosting for extra sweetness, or simply enjoy them as-is. Leftovers will keep in an airtight container for a few days.
Chewy Black and White Blondies
1/4 cup sugar
1/4 cup unsweetened cocoa powder
1/2 tsp instant coffee or espresso powder
3 tbsp water, warm
2 1/2 cups all purpose flour
1/2 tsp baking soda
1/2 tsp baking powder
1 tsp salt
1/2 cup butter, room temperature
1 1/2 cups sugar
2 large eggs
2 tsp vanilla extract
3/4 cup mayonnaise
Preheat oven to 350F and grease a 9×13-inch baking pan. Line base of pan with parchment paper for easier removal.
In a small bowl, combine 1/4 cup sugar, cocoa powder, hot water and instant coffee. Whisk to combine and set aside.
In a medium bowl, whisk together flour, baking soda, baking powder and salt.
In a large bowl, cream together butter and 1 1/2 cups sugar until light and fluffy. Beat in eggs one at a time, followed by the vanilla and mayonnaise. Blend in the flour mixture, stirring until no streaks of flour remain.
Transfer 1 cup of batter to the small bowl containing the cocoa mixture and stir until uniform.
Spread vanilla batter into prepared pan. Top with chocolate batter and drag a knife through to create a swirling pattern (don’t over marble, though!).
Bake for about 30 minutes, until a toothpick inserted into the center comes out clean or with only a few moist crumbs attached.