Butter contributes milk solids and water to a cookie, both of which soften it. Brown sugar contributes molasses – again, a softener. Using lower-moisture sugar (granulated) and fat (vegetable shortening), plus a longer, slower bake than normal, produces light, crunchy cookies.
If your cookies are flat, brown and crispy, that means you need to add flour to your dough for the next batch. Though the culprit is usually a flour deficit, butter could also be to blame for this problem. Adding too soft or slightly melted butter to the dough can also result in flat cookies.
What makes cookies soft and chewy? High moisture content does; so the recipe, baking time, and temperature must be adjusted to retain moisture. Binding the water in butter, eggs, and brown sugar (it contains molasses, which is 10 percent water) with flour slows its evaporation.
Keep those cookies crisp by storing them in an airtight container. Some people toss a piece of bread in with the cookies to help absorb any excess moisture. You could also re-crisp them by baking on a wire rack in a 300 degree F oven for a few minutes.
Cookies bake quickly — usually within 8 to 10 minutes — but sometimes it’s hard to tell when they’re baked through. You can always return cookies to the oven if they need a few more minutes. You can even rebake cookies long after they’re cool to restore crispness or freshness.
Reasons cookies are browning too quickly and raw in the middle. Your cookies might be browning too quickly because of: your oven: it might not be preheating to the set temperature and might be going way above that or you are setting your oven to a very high temperature, too high for your cookies.
Look at the sheen.
As the dough melts it gets glossy. Dry around the edges, golden brown around the bottoms, and the top is just losing that glossy sheen. There is a teeny bit left but that keeps them gooey. The center will set and fall a bit as these cool and they’ll be soft for days.
Look for golden edges.
The centers may remain a soft golden hue, while the edges may turn more dark gold or light brown. Make sure to remove the cookies before the edges turn dark brown or they’ll be burnt. For example, you can test the doneness of peanut butter, oatmeal, and other drop cookies by using this method.
Place one baking sheet at a time onto center rack of preheated 350 degree F oven. Bake until cookies are golden around the edges, still have pale tops, and are soft in the center, about 8 to 10 minutes. (Do not overbake!
Bake at 375 degrees F until golden and tender, 12 to 15 minutes. For crispy-cakey cookies: Bake the cookies at 425 degrees F until golden and crunchy on the outside, 8 to 10 minutes.