In a medium size mixing bowl, add runny peanut butter, melted coconut oil, powdered erythritol and unsweetened cocoa powder.
Combine with a spoon until the batter is smooth and consistent. Taste the batter and adjust sweetness to your liking. You can add up to 4 tablespoons of powdered erythritol or few stevia drops to boost sweetness. This won't impact the net carbs per serve.
Fill evenly each muffin case with the fat bomb batter. One fat bomb will be the size of about 2 to 2.5 tablespoons of batter.
Freeze the whole muffin tray for 15 minutes or until the fat bombs are solid.
Remove from the freezer, and store the fat bombs in the fridge, in an airtight container for up to 2 weeks or keep in the freezer and defrost 30 minutes before eating.
You can eat these fat bombs frozen, half-frozen or cold, straight out of the fridge. They soften at room temperature so you must store them in the fridge or freezer. I recommend a pinch of salt on top of the fat bombs for adding taste!