Melt the chocolate using a microwave or double boiler until smooth.
Line a muffin tray with cupcake liners.
Pour a small layer of melted chocolate into each liner and spread evenly.
Refrigerate for 10–15 minutes until set.
In a bowl, mix peanut butter, powdered sugar, melted butter, vanilla extract, and salt until smooth.
Add a layer of peanut butter mixture over the set chocolate.
Cover with another layer of melted chocolate.
Refrigerate again until fully set (about 20–30 minutes).
Remove from liners and serve.