Made Chewy Chocolate Chip cookie dough on Sunday and learned a valuable lesson. Chilling the dough is very important. Observe these two pictures.

flat cookies

vs.

puffy cookies

The picture on the top is when I cooked the cookies right after I made the dough. Very flat.

Picture on the bottom is when I cooked them after they had been in the fridge for 15-20 minutes.

I just pulled a batch out of the oven made with do chilled since Sunday and they are not flat.

Update:

Metric version of the recipe.

Non-metric version of the recipe.