Microwave brownie in a mug

Step by Step

Step 1

Place the butter and chocolate chips in a mug (an 8-ounce mug is the perfect size, but larger will work too) and melt in 20-second increments in the microwave, on high power, stirring in between, until the chocolate is mostly melted, about 40 seconds total. Using a small spoon, stir until completely smooth. Stir in the sugar, vanilla, and salt. Add the egg yolk and stir until smooth. Stir in the flour until smooth and shiny. Using a paper towel, wipe down the batter on the inside edges of the mug.

Step 2

Microwave, uncovered, on high power for 45 to 55 seconds until puffed and set. (You may need to adjust the time for less or more powerful microwaves.)