Preheat oven to 350-degrees and grease a 9" x 13" baking dish.

Sift the flour, cocoa, and salt, and set aside.

In a large bowl, add the sugar and melted butter and mix.

Next, add the vanilla extract, and eggs, one at a time, and mix.

Add the flour mixture and mix well.

In a small bowl, add the chocolate chips and teaspoon of flour and toss. Add the chocolate chips to the batter and mix well.

Pour the batter into the baking dish.

In another bowl, add the peanut butter and melt in the microwave for about 30 seconds. Add more time, in increments of 10 seconds, if needed.

Pour the peanut butter over the brownie batter and run a knife through to create the swirls.

Bake for 35 minutes or until the cake tester comes out clean.

Cool for about 30 minutes before slicing.