Chocolate

Double Chocolate Fudge Mug Cake

Dense, glossy, and deeply chocolate. More brownie than cake in the best way.

  • Prep 3 min
  • Cook 1m 25s
  • Total 5 min
  • Difficulty Easy
  • Eggless
Double chocolate fudge mug cake with glossy melted chocolate chips on top

Steps

  1. Whisk flour, cocoa, brown sugar, baking powder, and salt in a 12 oz mug until the cocoa streaks disappear.

  2. Add milk, oil, and vanilla. Stir from the bottom until the batter looks glossy and thick, about 25 seconds.

  3. Fold in 1 tablespoon of chocolate chips, then scatter the remaining tablespoon over the top so the surface bakes shiny.

  4. Microwave on high for 75-85 seconds. Stop when the edges look set and the center still has a soft wobble.

  5. Rest for one minute. The center tightens into a fudgy spoonable crumb instead of drying out.

Tips from the test kitchen

Brown sugar is doing real work here: it pulls moisture into the crumb and keeps the center soft after the microwave stops.

Success guide

Make it work the first time

Expected texture

Expect a soft, spoonable crumb rather than crisp edges. Chocolate mug cakes cook like tiny steamed cakes, so the best cue is a set edge with a slightly soft center.

Success tips

  • Use a microwave-safe mug with visible headroom. If the batter fills more than about half the mug, move it to a larger mug before cooking.
  • Start with the lower end of the microwave time in the steps. Add time in short bursts only if the center still looks wet.
  • Let the cake rest before eating. The crumb keeps setting after the microwave stops, and the mug will be very hot.
  • This recipe avoids a whole egg, which helps prevent the bouncy texture people often dislike in small mug cakes.

Substitutions

Milk
Whole milk gives the softest crumb. Unsweetened oat or almond milk can work, but the cake may taste a little lighter.
Fat
Neutral oil keeps mug cakes moist. Melted butter works in some chocolate or vanilla cakes, but it can make the crumb firmer as it cools.
Flour
Do not assume a direct gluten-free flour swap unless the blend is labeled cup-for-cup; the texture may turn gummy.
Mix-ins
Keep heavy mix-ins near the center of the batter. If they touch the mug wall, they can overheat before the cake finishes.

Troubleshooting

Rubbery texture
Usually caused by overmixing, overcooking, or too much egg for one mug. Mix only until no dry flour remains and stop at the first set-top cue.
Dry crumb
The cake likely cooked too long. Next time start at the low end of the time range and let rest instead of microwaving until fully dry.
Overflow
The mug was too small or too full. Use more headroom and set the mug on a paper towel if your microwave runs hot.
Wet center
Microwave in one short burst, then rest again. A slightly glossy center is fine; a puddle of batter needs more time.

Variations

  • Add a pinch of instant espresso to make the cocoa taste deeper.
  • Drop extra chocolate chips in the center for a softer spoonful.
  • Scatter a few chips on top before cooking for a softer, glossier surface.