Holiday treat #3

A while ago when we were stopped at a gas station on our way back from Utah, we discovered mini Reese's peanut butter cups. They were delicious on their own, but I though they'd be even better in brownies. The other day when we were at the store I saw that they were being sold in big pouches, so I bought one and made up a batch of these- 

Deep Dark Peanut Butter Cup Brownies
Ingredients
1 c. (2 sticks) unsalted butter
2¼ c. granulated sugar
4 large eggs
1¼ c. Dutch-process cocoa
1 tsp. salt
1 tsp. baking powder
1 tsp. espresso powder (optional)
1 tbsp. vanilla extract
1½ c. unbleached all-purpose flour
1 c. chocolate chips
1 c. mini Reese's peanut butter cups chopped in half

DIRECTIONS:
1. Preheat oven to 350 degrees and lightly grease a 9" x 13" pan.
2. In a medium-sized sauce pan over low heat, melt butter, remove from heat and then add sugar and stir to combine. Return the mixture to heat until it is hot but not bubbling. It will become shiny and glassy. Continue to stir.
3. While the mixture is heating for the second time, crack 4 eggs into a large mixing bowl and beat them with the cocoa, salt, baking powder, espresso powder, and vanilla until smooth.
4. Add the butter/sugar mixture and combine, stirring until smooth.
5. Add the flour, stirring until smooth. Wait until mixture has slightly cooled (10 minutes or so) to add chocolate chips and peanut butter cups.
6. Pour batter into the greased pan and bake for 30-35 minutes until a cake tester inserted into the center of the pan comes out clean. The brownies should look set and crusty around the edges and the middle should look moist and shiny.
7. Remove from oven and cool on rack for 30 minutes before serving.
Adapted from King Arthur Flour, Deep-Dark Fudgy Brownies | Makes approximately 24 bars