How to Make the Perfect Chocolate Chip Cookie, According to Science

Flat and Tender

Skip the shortening and just use butter (and plenty of it). The fat in butter is essential for tenderness, and the small amount of water in it will make your cookie spread out on the cookie sheet. Shortening, on the other hand, is better for those who like their chocolate chip cookies to taste super soft and dense, similar to a store-bought one. Butter is absolutely essential for flavor, too. If you dare replace it with Crisco, lard, or margarine, you'll seriously compromise the taste of your cookies.

Chewy Cookies

Subbing in bread flour for all-purpose will give you a chewier cookie, thanks to its higher protein (and gluten) content. On the other hand, if you're partial to super soft cookies, try using lower-protein cake flour. You can also toy with varying proportions of the two until you nail your 'just right' cookie.

Thin and Crispy

Use all granulated white sugar. If a recipe calls for brown and white sugars, substitute an equal amount of white for the brown. White sugar helps absorb moisture in the dough, resulting in crisper cookies. And as it heats and dissolves, it causes the cookies to thin out.

Thick and Moist

Use all brown sugar: the reverse of thin and crispy. Brown sugar contains molasses, which adds moisture to the cookies. Molasses is also slightly acidic, which causes the proteins in the dough to firm up quickly instead of spreading out.

RELATED: 5 Smart Substitutes for Brown Sugar

Soft With Crisp Edges

Stick to equal parts granulated white sugar and brown sugar. The granulated sugar causes just enough spread for the edges to firm up, while the brown sugar softens the middle for that irresistible chew.