01 - Line a 12-cup mini muffin tin with paper liners.
02 - Melt the chocolate and coconut oil together in a heatproof bowl set over a pan of simmering water, or microwave in 30-second intervals, stirring until smooth.
03 - Spoon about 1 teaspoon of melted chocolate into the bottom of each liner. Tilt the tin to evenly coat the base. Place the tin in the freezer for 10 minutes to set.
04 - Mix the peanut butter, powdered sugar, butter, vanilla, and salt in a bowl until smooth and thick.
05 - Roll 12 small balls (about 2 teaspoons each) of the peanut butter mixture and flatten slightly into discs.
06 - Remove the tin from the freezer. Place one peanut butter disc in each cup, gently pressing down.
07 - Spoon the remaining melted chocolate over the peanut butter, covering it completely.
08 - Chill in the refrigerator for at least 30 minutes or until firm. Once set, remove from liners and store in an airtight container in the refrigerator.