Make the peanut butter filling:

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

Make the brownies:

1. Preheat oven to 175 degrees C. 
2. Line the square pan again with parchment paper, leaving an overhang.
3. In a large microwave bowl combine the butter and 113 grams of chocolate. Microwave for 30-seconds, stirring in between, until the mixture is melted and smooth. 
4. Add the sugar to the hot butter mixture and whisk until combined. Allow to cool until just barely warm. 
5. Add in eggs, yolk, and vanilla essence and whisk for about 1 minute, or until very well combined.
6. Use a rubber spatula to stir in flour, cocoa powder, and salt until combined.
7. Pour half of the batter into prepared pan and smooth out. 
8. Carefully place the frozen peanut butter sheet over the batter. Pour remaining batter on top, covering completely.
9. Bake in the preheated oven for about 25 minutes, or until cooked through but still very slightly gooey in the center. 
10. While the brownies are baking towards the end, add the rest of the dairy milk chocolate to the microwave with 1 tsp of butter until melted.
11. Once the brownies are baked after five minutes add your melted chocolate over with sprinkled peanuts.
12. Let cool in pan 30 minutes. Remove from pan and allow to cool for another 30 minutes before slicing and serving.