This is the best chewy blondie recipe! These cookie bars include the option of adding white chocolate chips and nuts, but they taste just as good without any add-ins!Be sure to check out the VIDEO at the bottom of the recipe!
Preheat oven to 350F (175C) and line a 13x9 pan with parchment paper**
Combine melted butter and sugar in a large bowl and stir well.
Add eggs, egg yolk, and vanilla extract and stir until completely combined. Set aside.
In a separate bowl, whisk together flour, cornstarch, baking powder, and salt.
Gradually stir dry ingredients into wet until completely combined.
Fold in white chocolate chips and nuts, if using.
Spread blondie batter into prepared pan and transfer to oven.
Bake on 350F (175C) for 25-30 minutes*** or until a toothpick inserted in the center comes out clean or with a few fudgy crumbs.
Allow to cool before cutting and enjoying
* I like to use half dark and half light brown sugar in this recipe. You can use all light or all dark, either will work, but if you use all dark brown sugar the blondies will be a bit richer, sweeter, and more moist.**If you don't have parchment paper you can lightly grease and flour the sides and bottom of your pan instead. ***If you use a glass pan it will likely take longer than the suggested time to bake.