Chocolate chip cookies. Everyone loves them. Making them is child’s play, but making them the archetypal crispy-ooey-gooey chocolate chip cookies of the gods? Now that’s serious business. So we set out to take on the challenge of making incredible chocolate chip cookies easier for you.

In the 1930s, a woman named Ruth Wakefield decided to tweak an old colonial recipe for chocolate cookies at the Toll House Inn in Massachusetts. She had a degree in household arts and she was perpetually developing better recipes for the food she fed her guests. She tried replacing baker’s chocolate with chunks of a new semi-sweet chocolate bar, given to her by a man named Andrew Nestlé. Ooey-gooey patches of chocolate stayed intact in the cookies. You know they were an immediate hit.

By 1938, she was asked to write a cookbook of her recipes, Toll House Tried and True Recipes. By 1939, the recipe was so voraciously popular that Nestlé started producing small chips of chocolate for people who wanted to make the recipe. And we have all been baking and eating chocolate chip cookies by the dozen ever since.

We love that the original chocolate chip cookie recipe came out of the same kind of approach we have here at ChefSteps: deep curiosity, scientific training, and a spirit of play.

However, it has been 80 years since she first served those cookies to her guests. In the last decade, recipe developers and pastry chefs have been tweaking the chocolate chip cookie to make it even more delicious. We believe we can help with that.

Let’s be honest. We thought at first that we could create the Ultimate Chocolate Chip Cookie. But here’s the deal: there is no one right cookie. Everyone has a different palate. Some people love a shattery crisp cookie. Some of us love cookies with heft and chew. Some people prefer milk chocolate while others love chocolate with over 72% cacao. Soft, squishy, thin, large, tiny, sweet, salty—chocolate chip cookies come in all types and sizes. Chasing the Ultimate Chocolate Chip Cookie is silly, in the end.

So, we decided instead to make the Ultimate Guide to Chocolate Chip Cookies. We set out to create the best resource for anyone who wants to make a great chocolate chip cookie.

First, we found our 10 Best Chocolate Chip Cookie Recipes. These are the recipes created by chefs and recipe developers we trust, recipes that always perform well on internet searches, recipes that each had something particular the recipe developer wanted to add to the chocolate chip cookie pantheon. We compared them. We baked them. We analyzed them.

Next, our chefs made a LOT OF COOKIES. (At last count, 1,000 cookies in 4 weeks.)

We tested every ingredient in a cookie in every way we could. We tested different processes of mixing, resting the dough, baking, and cooling. We realized that, in terms of the final cookie, being particular about the process is far more important than the quality of any individual ingredient. We learned important lessons. We did all these trials to get to the bottom of how the very best formula for making chocolate chip cookies might function.

And one day, playing with the parametric of the formulas for all the cookies, Chef Grant Crilly decided on a whim to average all the percentages into a new formula. Chef Matthew Woolen baked that recipe and we ate the cookies. To everyone’s surprise, it ended up being the best chocolate chip cookie we had ever tasted. There was no logical reason for it to work. But it became the Ultimate Average Chocolate Chip Cookie.

And then, after all those weeks of work, and hundreds of baked cookies, we learned so much about how to make a cookie chewy or crisp, sweet or salty, thin or thick that we put all those lessons into a Chocolate Chip Cookie Calculator for you. You can take any of the recipes we like best, make the dough, and make a crisp cookie, a soft cookie, a small cookie, or a large cookie.

We want to help you make the best chocolate chip cookie you have ever tasted. And we want it to come from your kitchen.

Welcome to the Ultimate Guide to Chocolate Chip Cookies.

And thanks, Ruth Wakefield, for starting it all.