Add the butter to a mug and microwave for 20 seconds to melt.
Add remaining ingredients in the mug and mix well using a fork until fully incorporated and there are no clumps.
Microwave on high for 60 seconds.
Optionally, top with whipped cream, powdered erythritol, keto ice cream or my personal favorite, peanut butter! Serve immediately in the mug or flip out onto a plate, and enjoy
Tip: 50 seconds will give you a slight lava center!