This is one of my favourite recipes to make because it is the perfect, yummy chocolate fix! I first stumbled across it when doing a Chemistry project in grade 11, and ever since then I have been making it. Sometimes I have to hide cookies for myself because they get eaten so quickly! Sometimes I don't wait the 2 hours for the dough to firm in the fridge because I'm too impatient! You can just add a little extra flour and the cookies just turn out a little less puffed up, but still great!