Add the hot coffee and vanilla extract to a large mug, then add the erythritol and stir well to dissolve. At this point, you may omit the sweetener or use your preferred low-carb alternative if desired. Add the cacao butter and unsalted butter to the hot coffee, stir well to combine, melting the fats into the coffee.
Step 2
You may taste and adjust the sweetener if needed. Carefully use a handheld stick blender or a milk frother to blitz the coffee until creamy and frothy on top. Once blended, serve the coffee immediately.