Melt all ingredients together and stir. Set aside.
Make the Roll
Melt the butter, then add the egg and mix.
Add the remaining ingredients and mix.
Add half of the glaze to the roll mixture and stir to swirl it in. The mix should not pass the halfway mark of the mug or it will overflow.
Microwave 40-90 seconds depending on your microwave. It'll rise quickly, and it may look like it's going to overflow. Once you see it not rising anymore, let it go for 3 more seconds, then stop.
Make the Icing
Microwave the ingredients for 15 seconds or so and stir. Don't wait for the icing to completely melt, because it'll overcook. Take it out and stir to see if it's the right consistency.
Pour the remaining glaze and icing on top.
Notes
I do not recommend substituting an alternate fat for the butter. Butter really develops the flavor and richness in this cake.Equipment: 2 Small Bowls, 1 Mug/Ramekin, Spoon.