Start by melting the chocolate chips. You can do this in a microwave or over a double boiler.
In another bowl, combine the peanut butter, softened butter, powdered sugar, and vanilla. Mix until smooth and slightly thick
Line a standard muffin tin with 12 paper cupcake liners. If you want smaller, bite-sized versions, use a mini muffin pan instead.
Spoon about 1 teaspoon of melted chocolate into the bottom of each liner. Use the back of the spoon to spread it evenly so it coats the base.
Place the pan in the freezer for 5–7 minutes until the chocolate hardens slightly.
Once the base has set, scoop about 1 teaspoon of the peanut butter mixture and roll it into a small ball. Gently flatten it between your fingers so it forms a disk slightly smaller than the chocolate base.
Place it on top of the hardened chocolate layer in each cup. Press lightly to help it sit evenly but don’t push too hard — you want a nice, even middle layer.
Spoon another teaspoon of melted chocolate over each peanut butter layer, spreading gently to cover it completely. Tap the muffin tin lightly on the counter to help the chocolate smooth out and fill in any gaps.
Once done, refrigerate or freeze for about 15–20 minutes, until fully set.
