Preheat the oven to 350°F (175°C). Grease a 9x13 inch baking pan.

In a mixing bowl, cream together the softened butter, granulated sugar, and brown sugar until smooth.

Add the peanut butter and mix until well combined.

Beat in the eggs one at a time, then stir in the vanilla extract.

In a separate bowl, whisk together the flour, baking powder, and salt.

Gradually add the dry ingredients to the wet ingredients, mixing until just combined.

Spread the batter evenly into the prepared baking pan.

Bake in the preheated oven for 25 minutes or until golden brown.

Remove from the oven and immediately sprinkle chocolate chips over the top.

Drizzle melted peanut butter over the chocolate chips.

Allow to cool completely in the pan before cutting into bars.