Prepare coconut butter and set aside (see link in ingredients).
Add 2 inches of water to a medium saucepan and bring to a rolling simmer over medium-high heat. Then reduce heat to medium and set a medium glass or ceramic mixing bowl on top, making sure it's not touching the water (this creates a "double boiler").
To the mixing bowl, add finely chopped cocoa butter and coconut oil and let melt, stirring occasionally with a wooden spoon or whisk - about 2-3 minutes.
Once melted, carefully remove bowl from heat (turn off stove) and add maple syrup. First add cacao or cocoa powder to a sifter and sift over mixture. Then use a whisk or wooden spoon to mix until smooth and thoroughly combined. At this time, add optional sea salt and vanilla if desired.
Taste and adjust flavor as needed. I added about 2 Tbsp maple syrup total (amount as original recipe is written // alter if adjusting batch size), but it’s completely up to how sweet you prefer your chocolate.
Because the chocolate is quite thin at this point, set in the refrigerator to chill, slightly thicken, and make coating the cupcake wrappers easier - about 15-20 minutes total, removing to stir/whisk occasionally. You'll know it's ready when it's more like pourable hot fudge than melted coconut oil.
Line a standard muffin tin with 10 (alter amount if adjusting batch size) paper cupcake liners and add 2 Tbsp (~30 g) of the chocolate to each. Use a spoon to gently push some of the chocolate up so it slightly coats the paper liners. Then set in the refrigerator or freezer to chill for 10 minutes.
Once the chocolate is slightly firmer, add 1 1/2 Tbsp (~27 g) coconut butter to each. Then set back in the refrigerator or freezer to chill for 10 minutes or until the coconut butter is slightly hardened to the touch.
Add remaining chocolate (~1 1/2 Tbsp each) on top of the coconut butter and use a spoon to ensure that the coconut butter is fully covered. Then set back in the refrigerator or freezer to chill for 10-15 minutes or until the cups are firm to the touch.
Enjoy straight from the refrigerator or freezer. Or let set out and thaw for 10-15 minutes and enjoy at room temperature for a softer coconut butter cup (my favorite).
Store leftovers in the refrigerator up to 2 weeks or in the freezer up to 1 month.
Notes
*If you don't want to make your own chocolate, simply substitute 1 1/2 cups finely chopped vegan dark chocolate. *Nutrition information is a rough estimate calculated with coconut oil.