Put all the dry ingredients in the mug and mix well.
Add the egg and mix as best you can.
Add the milk and the oil and mix until nice and smooth.
Add the chocolate chips and mix again.
the mug in the microwave and cook for 3 minutes on high. Don't worry if the cake rises over the top of the mug, it's fine!
Remove from oven and let cool for a little.
Turn out onto a small plate.
For a little something extra, drizzle with some caramel sauce. Mmmm!