Line a large cookie sheet with parchment paper. Set aside.

Slice the cake into 12 pieces, Using a 1 ½-inch biscuit cutter, cut 2 circles from each cake slice. Place circles on a large cookie sheet (not the one lined with paper). Set aside

Scoop peanut butter into a large plastic resealable bag. Squeeze the air out and seal the top. Cut a small corner of the bag. Pipe peanut butter on top of each cake circle. Smooth the peanut butter with a small spatula or butter knife. Place in freezer for 30 minutes. (If you're in a hurry, you can skip this step. It makes it easier to dip though.)

After you take the cakes out of the freezer, you're ready to melt the chocolate. Place the chocolate in a large microwave safe bowl. Microwave on high for 2 minutes. Stir until smooth. If you need to, you can microwave it for another 15-20 seconds.

To dip, drop a cake bite in the chocolate (peanut butter side up). Use a fork to push the chocolate up and over the cake (make sure you don't touch the cake though, you don't want crumbs in your chocolate). Once it's covered in chocolate, lift the cake with the fork and tap off excess chocolate. Place on cookie sheet lined with parchment paper. Decorate with sprinkles, if desired. Once you've dipped (and decorated) all of the cakes, place them in the refrigerator for 30 minutes to 1 hour or until set.

Store covered in refrigerator for up to 5 days.