I attended pastry school in France. Here are 8 tricks I've learned for making the perfect cookies.

• I’ve found that using a kitchen scale and buying a pricier butter leads to delicious results.
• For decadent chocolate chip cookies, I always like to add an extra egg yolk to the dough.

I like to splurge on higher-quality butter for richer cookies.

Resting the dough in the fridge is an important step.

The yolk adds extra fat and richness to the dough without much additional water, resulting in a softer, chewier cookie with a richer overall flavor.