1 tablespoon of white sugar
1 tablespoon of packed brown sugar
3 drops of vanilla extract
1 dash of salt
1 egg yolk (not the egg white!)
scant 1/4 cup of flour (don't fill the cup all the way... just a bit less!)
2 tablespoons of chocolate chips!
1. Melt butter in a mug in the microwave
6. Cook in microwave for 45-60 seconds - depending on the power of your microwave!