Place the pound cake on a sheet of wax paper and set aside.
Combine the butter and peanut butter in a microwave safe bowl and microwave for 30 seconds, or until butter is melted. Stir until smooth and then stir in the powdered sugar and vanilla extract, stirring again until smooth.
Spread half of the peanut butter mixture on top of the pound cake and place in the fridge for 3 minutes. Spread the rest of the peanut butter mixture on top of the pound cake and place back in the fridge for 3 minutes to harden.
Melt the chocolates according to package instructions and then pour evenly over the top of the pound cake, letting it run down the sides. Let harden before slicing. Enjoy!