Preheat oven to 375 degrees
Line a 9”x 13” baking pan with foil, including sides, so brownies can be lifted out after baking. You will also need to spray the foil with a non-stick spray. See notes for the optional baking pan I like to use. In a medium-sized saucepan, combine sugar and butter. Cook over medium heat, stirring often until butter melts and sugar dissolves.
Remove from heat and let it sit to cool slightly.
Once it has cooled slightly add the 2 eggs and vanilla, whisk mixture well.
In a small bowl combine flour, baking powder, and salt.
Add flour mixture to sugar mixture and stir to combine.
Fold in chocolate chips, then spread into prepared pan.
In a small bowl beat cream cheese with the egg yolk then add peanut butter and mix until creamy.
Drop spoonfuls of peanut butter mixture over batter in baking pan.
The mixture is thick but try to swirl the peanut butter mixture through the brownie mixture trying not to scrape the bottom of the pan.
Bake for 25 minutes or until a toothpick inserted comes out clean.
Remove from oven and cool on a wire rack.
When brownies reach room temperature, lift them from the pan, holding onto the edges of the foil. You can also refrigerate them before lifting out of the pan to make it easier.
Cut into squares. Enjoy at room temperature or chilled.
Store peanut butter two-tone bars in the refrigerator or freezer. These are outrageous frozen!