Place the vanilla wafers in a food processor and pulse until crushed into fine crumbs, about 1-2 minutes.
Add in the powdered sugar to food processor and pulse 1-2 times until combined.
Add 1 cup of the divided peanut butter, melted butter, and vanilla extract to the food processor and blend together until a smooth, thick dough forms, about 2-3 minutes.
Line an 8x8 inch baking pan with parchment paper, then scoop in the peanut butter dough.
Press the dough down into an even layer in the prepared pan, cover it with plastic wrap, and place it in the refrigerator to chill.
Next, place the cup chocolate chips and the remaining ¼ cup of creamy peanut butter in a microwave-safe bowl.
Heat for 60 seconds and then stir until smooth. If it doesn’t smooth out completely, you can continue heating in 10-second increments, stirring well each time, until smooth. Do not overheat.
Pour the chocolate mixture over the top of the peanut butter layer and use a spatula to smooth it into an even layer.
Cover the pan with plastic wrap and place the pan into the refrigerator and allow to chill until set, about 3-4 hours.
Once completely set, cut into squares and serve.