Add dry ingredients to mug, mix well.
Add the egg and mix throughly
Pour in the milk and oil and mix well
Add the chocolate chips and vanilla, mix
Put the mug into the microwave and cook for 3 minutes at 1000 watts
The cake will rise over the top of the mug. Don't be alarmed!
Allow to cool. You can tip the cake onto a plate, if you want or just eat out of the mug
Add additional chips, chocolate syrup and/or whipped cream
Seen recently on a tee shirt:
EMERGENCY ALERT: If wearer of this shirt is found vacant, listless, or depressed, ADMINISTER CHOCOLATE IMMEDIATELY.