Preparation
In a small saucepan, combine the butter, coconut oil, sugar-free blueberry syrup, and unsweetened cocoa powder.
Place the saucepan over low heat.
Whisk continuously until all are fully melted and the mixture is smooth, glossy, and well combined.
Do not allow the mixture to boil.
Carefully pour the liquid chocolate into a silicone mold, such as an ice cube tray or mini muffin pan.
Transfer the mold to the freezer and let it set for at least 3 hours, or until completely firm.
Once solid, gently pop the fat bombs out of the mold.
Enjoy immediately or store in the freezer.