Preheat oven to 375°F and line a 9x13-inch pan with parchment paper.
In a large bowl, cream together both kinds of peanut butter, butter, granulated sugar, and brown sugar with a handheld mixer on medium speed until well blended.
Beat in the egg and vanilla, scraping the sides of the bowl as needed.
In a separate bowl, whisk together the flour, baking powder, and salt; mix into the creamed mixture.
Spread ⅔ of the peanut butter dough onto the bottom of the 9x13-inch pan.
Spread the preserves evenly over the bottom layer of dough.
Dollop the remaining dough evenly over the top of the preserves.
Top with the chopped peanuts.
Bake for 30-35 minutes, or until the edges are golden brown.
Let cool completely before serving.