Preheat the oven to 350°F, and line a 9x13 inch baking pan with parchment paper. Set aside.
In a large bowl, use a hand mixer to cream the butter until fluffy. Then, add the brown sugar and granulated sugar, and mix until combined.
¾ cup unsalted butter, 1 ½ cup light brown sugar, ¼ cup granulated sugar
Add the eggs and vanilla, and beat until completely incorporated.
3 large eggs, 2 teaspoons pure vanilla extract
Mix in the flour, baking powder and salt until a thick dough forms. Use a spatula to fold in both kinds of chocolate chips.
2 ⅓ cup all-purpose flour, 2 teaspoons baking powder, ½ teaspoon kosher salt, 1 cup milk chocolate chips, 1 cup semi-sweet chocolate chips
Press the dough into the prepared baking pan, and bake for 20-25 minutes or until light and golden on top.
Allow the bars to cool for 20-30 minutes before slicing and serving.
See post for storage options.
Notes
*The calories listed are an approximation based on the ingredients in the recipe card and a serving size of 1 congo bar. Actual calories will vary.*For more information, tips, and answers to frequently asked questions, please refer to the post.*Photos courtesy of Karla Rae Photography.