1. Preheat oven to 350 degrees.
2. Prepare a 9 by 9 inch baking pan by lining it with parchment paper, leaving excess hanging over the sides for easy removal later.

Brownie Batter

1. In a small pan over medium heat, melt butter and stir in sugar.
2. Remove from heat and stir in eggs and vanilla extract. Set aside.
3. In a medium bowl, mix flour, cocoa powder, salt and baking powder. Stir the butter, sugar and eggs into the dry ingredients until just mixed. A few lumps are okay.
4. Pour the brownie batter into the pan and set aside.

Peanut Butter Cookie Dough

1. In a medium bowl, whisk together vegetable oil and sugar. Then add the egg, vanilla extract, and peanut butter and mix well.
2. In a separate bowl, mix the flour, baking soda and salt and then add to the wet ingredients to form a dough.
3. Drop 25 scoops of peanut butter cookie dough (about 1 TB each) onto the brownie batter.
4. Bake for 27-30 minutes, then cool completely before cutting into bars.