| Preheat the oven to 350 degrees F. Line a 9x13 pan with foil. Spray foil with non-stick cooking spray. In a large bowl, melt butter. Whisk in sugar and water. Add eggs, oil and vanilla and stir until combined. Add half of flour and the baking powder. Place peanut butter in a small bowl. Add in 1 cup of the batter; stir until smooth. In another small bowl, combine the remaining flour with the cocoa. Combine into remaining batter. Stir in chocolate chips. Pour chocolate batter into prepared pan. Drop peanut butter batter by teaspoonfuls onto chocolate batter. Using a knife, swirl together. Bake for 20-25 minutes or until top springs back when touched lightly. | 
