Black & Whites

2 1/4 cups all-purpose flour
1/2 cup unsweetened cocoa powder
1/2 teaspoon baking soda
1/4 teaspoon salt
1 cup dark brown sugar, firmly packed
3/4 cup white sugar
1 cup salted butter, softened
3 large eggs
2 teaspoons pure vanilla extract
1 cup (5 1/4 oz) semi-sweet chocolate chips
1 cup (5 1/4 oz) white chocolate chips

Preheat oven to 300oF.

In medium bowl, combine flour, cocoa, soda and salt. Mix well with a wire whisk. Set aside.

Blend sugars in a large bowl using an electric mixer set at medium speed. Add butter and mix to form a grainy paste, scraping down the sides of the bowl. Add eggs and vanilla, and beat at a medium speed until smooth. Add the flour mixture and chocolates, and blend at low speed until just combined. Do not over-mix. Drop by rounded tablespoons onto ungreased cookie sheets, 2 inches apart. Bake 23-25 minutes. Transfer cookies immediately to a cool, flat surface.