Melt the Chocolate:In a microwave-safe bowl or double boiler, melt the chocolate chips with 1 tablespoon of coconut oil. Stir until smooth and set aside.
Prepare the Peanut Butter Filling:In another bowl, mix peanut butter, remaining coconut oil, sweetener, and vanilla extract until well combined.
Assemble the Cups:Spoon about 1 teaspoon of melted chocolate into each mini muffin liner. Gently tilt or tap the liner to coat the bottom evenly. Place in the freezer for 10 minutes to firm.
Add the Peanut Butter Layer:Once the chocolate has set, spoon about 1 teaspoon of the peanut butter mixture on top. Smooth the surface.
Top with More Chocolate:Cover the peanut butter layer with another teaspoon of melted chocolate. Tap the mold again to level.
Chill to Set:Refrigerate or freeze the cups for at least 30 minutes until firm.
Serve or Store:Once set, enjoy immediately or store in an airtight container in the fridge or freezer.