Microwave Chocolate Banana Oat Mug Cake
A dense, fudgy single-serving mug cake made with mashed banana, oats and melted chocolate. Ready in minutes with no oven and no leavening, so it stays rich and spoonable.
- Total
- 10 min
- Prep 5 · Cook 3 · Rest 2
- Serves
- 1
- Difficulty
- Easy
You'll practice: Folding
- Sweet
- Quick
- Microwave
Instructions
-
Mash the banana in the mug with a fork until smooth, with only small lumps left.
~2 min
Mashing the banana releases moisture and natural sugars, which keeps the cake dense and fudgy without added liquid.
-
Stir the oats, peanut butter, water and salt into the mashed banana until no dry oats remain.
~1 min
-
Break the chocolate into a small microwave-safe bowl and microwave in 20-second bursts, stirring between each, until melted and smooth, about 1 minute total.
~1 min
Melting in short bursts with stirring prevents overheating, which can cause chocolate to seize into a grainy, unusable paste.
Melt the chocolate just until fluid; overheating it makes it seize into a grainy paste that will not blend smoothly into the batter.
-
Stir the melted chocolate into the mug until the batter is evenly dark and thick.
~1 min
Folding Fold gently until just combined to keep the batter airy; overmixing can make the cake dense and tough.
-
Microwave the mug on high for 90 seconds. The cake is done when the top looks set and slightly dry at the edges but still soft in the centre; if it is still wet, microwave in 15-second bursts.
~2 min
Microwaving sets the structure; stopping when the edges are set but the centre is soft keeps the cake moist and spoonable.
Microwave wattages vary, so stop as soon as the edges look set. A slightly molten centre is the point of this dense cake, not a fault.
-
Let the mug cake stand for 2 minutes to finish setting, then eat it warm straight from the mug with a spoon.
~2 min
Standing allows residual heat to finish cooking the centre and lets the crumb firm up for a better texture.