Step 1

Place the peanut butter in a heat safe bowl and microwave for 20 to 30 seconds, or until pourable but not super hot.

Step 2

Line a metal 8-inch square pan with parchment paper, leaving an overhang. Spread the peanut butter into an even layer in the pan. Freeze for 1 hour or until solidified. Use the parchment to remove from pan and return peanut butter sheet to freezer. Keep frozen while making the brownie batter.

Step 3

Preheat oven to 350°F. Line the square pan again with parchment paper, leaving an overhang.

Step 4

In a large microwave-safe bowl combine the butter and chocolate. Microwave in 30-second bursts, stirring between each burst, until the mixture is melted and smooth. Add the sugar to the hot butter mixture and whisk vigorously until combined. Allow to cool until just barely warm.

Step 5

Add in eggs, yolk, and vanilla extract and whisk for about 1 minute, or until very well combined.

Step 6

Use a rubber spatula to stir in flour, cocoa powder, and salt until just combined.

Step 7

Pour half of the batter into prepared pan and smooth out. Carefully place the frozen peanut butter sheet over the batter. Pour remaining batter on top, covering completely.

Step 8

Bake in the preheated oven for about 30 minutes, or until cooked through but still very slightly gooey in the center. Let cool in pan 30 minutes. Remove from pan and allow to cool for another 30 minutes before slicing and serving.

Step 9

Brownies can be stored in an airtight container at room temperature for up to 3 days or in the fridge for up to 5 days. Serving chilled makes the brownies extra fudgy!