Prepare the Wafer Layers:
If you’re using large wafer cookies, break them into smaller pieces or use wafer sticks. Arrange the pieces in a rectangular or square shape on a baking sheet lined with parchment paper.

1. Melt the Chocolate:
   In a heatproof bowl, combine the chocolate chips, peanut butter (if using), and vegetable oil.
   Microwave the mixture in 20-30 second intervals, stirring in between until completely melted and smooth. If you prefer, you can melt the chocolate using a double boiler on the stovetop.
2. Assemble the Bars:
   Pour half of the melted chocolate evenly over the wafer layers, ensuring the layers are well coated.
   Place the tray in the refrigerator for 15-20 minutes to let the chocolate set.
3. Add the Second Layer:
   Once the first layer of chocolate has set, pour the remaining melted chocolate over the wafer layers to completely cover them.
   Smooth the chocolate with a spatula to ensure even coverage.
4. Set the Bars:
   Refrigerate the bars for at least 1 hour or until the chocolate is firm and set. If you’re in a hurry, you can place them in the freezer for 30 minutes.
5. Cut and Serve:
   Once the chocolate is fully set, remove the bars from the refrigerator. Using a sharp knife, cut them into bar-sized pieces.
   Serve immediately or store them in an airtight container.