½ cups all-purpose flour
½ cup whole wheat flour
½ cup cocoa powder
½ tsp baking powder
½ tsp baking soda
½ cup unsalted butter, room temperature
½ cup granulated sugar
1 cup brown sugar
2 large eggs
1 tsp vanilla extract
¾ cup chocolate chips
½ cup creamy peanut butter (I had a bit extra)
sprinkles for decorating, if you like
1. Line two baking sheets with parchment paper and set aside. Sift together flours, cocoa powder, baking powder, and baking soda. Set that aside, too.
2. Using a hand-held electric mixer or a stand mixer, beat butter, granulated sugar, and ¾ cup brown sugar on medium speed until light and fluffy. Add eggs, one at a time, mixing until fully combined between additions. Add vanilla and mix again.
3. Gradually add dry ingredients, mixing on low speed until fully combined (if you're using a hand-held mixer, you may need to switch to mixing with your hands toward the end). Add chocolate chips and mix again to evenly distribute. Cover bowl with plastic wrap and chill 15 minutes to firm slightly. Preheat oven to 350 F/180 C about 5 minutes before done.
4. In a small bowl, stir together peanut butter and remaining ¼ cup brown sugar.
5. Drop 1 tablespoon of the dough at a time onto baking sheets, spacing cookies about 2 inches apart. Make a thumbprint in the center of each cookie and fill it with the peanut butter mixture (don't use too much, or it will spill out). Top with a second tablespoon of carefully shaped dough. Mold dough to cover the surprise. Note: This makes pretty big cookies. For smaller cookies like the ones pictured, use half-tablespoons of dough instead.
6. If you like, dip the tops of the cookies in sprinkles. Bake until firm, about 12 minutes, rotating halfway through. Let cool at least 5 minutes before moving.