Do not replace butter with other fats (eg. shortening, margarine, lard). The proteins in butter are essential to the flavors in your dough.
Melted butter will produce denser cookies while creamed butter will make cakier cookies.
Cookies made with browned butter will come out softer because of less gluten development. However this may cause it to break more easily.
A higher proportion of egg white to egg yolk will result in a taller cookie while a higher egg yolk to egg white ratio will result in a more dense, brownie-like cookie.
White sugar is pure crystallized sucrose. Brown sugar is mostly sucrose, but also contains glucose and fructose (more hygroscopic than sucrose) with trace minerals that give it flavor and a slightly acidic pH.
|Cookies made with 100% white or 100% brown sugar|
Cookies made with slightly acidic brown sugar cause them to rise more and spread less because the brown sugar reacts with baking soda (a base) to make bubbles that provide lift. Cookies made with white sugar do not leaven, but they are more crisp because sucrose does not hold water molecules as well as glucose and fructose.
Incorporate your chocolate chips halfway through the wet-dry mixing process to avoid over-mixing your dough. Excess kneading causes more gluten formation which can produce tough cookies.
Incorporating chocolate into dough that has been heated to 80 degrees F will allow some chocolate to melt, leaving chocolate trails in the cookie, while still leaving chunks intact to melt into pools of liquid delicious.
That $25 bottle of Madagascar bourbon vanilla extract is indistinguishable from imitation vanilla flavor.
Baking your cookies at a lower temperature will result in more spreading and more even cooking. But don't go too low, otherwise there will be not textural contrast between the edges and the center.
Leaving dough in the refrigerator overnight will allow time for flour proteins and starches to breakdown and rearrange so that your cookies have a richer flavor and more better browning.
|Cookies rested for four hours and two days before baking|
All photos: Serious Eats