Did you know that the original chocolate chip cookie was the result of a kitchen mistake? A housewife decided to pour melted chocolate into a cold dough to make a chocolate cookie. Instead the chocolate cooled and broke up into little chunks. These days most kitchen errors aren’t half as awesome or lucky. This post is here to help you prevent any chocolate chip cookie baking problems in your kitchen. How many different times have you seen a recipe calling itself “THE PERFECT CHOCOLATE CHIP COOKIE”? I know I’ve seen it more times than I can count. Is it the same recipe, printed over and over again? No, they’re often different (albeit only slightly.) How can this be? How can there be multiple perfect cookie recipes? Are all of these recipe writers wrong save for one? No way! The perfect chocolate cookie is totally subjective. I like mine dense and chewy, my boyfriend likes them light and crunchy (he is wrong, but I digress.) So here, instead of giving you another impersonal recipe I am going to show you how you can tailor the recipe to be your perfect cookie, be it chewy, crunchy, dense, sweet, or however you like it.

scienceofcookies-1aKelsey Kinser

There are many different components at play when making cookies. Let’s break them down. Most cookies call for:

sweeteners, like sugar or brown sugar

butter, softened and creamed, cold and cubed, or melted


flavoring, like vanilla extract


Flour, usually all-purpose

and a leavening agent like baking soda or baking powder.

Let’s take a deeper look at each of these components and the roles they play.

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White sugar dissolves easily and quickly in the water that is released from the butter as the butter begins to melt while the cookie bakes. This creates a cookie that spreads out thinner than one made with brown sugar or a mix of the two. A thinner cookie on a hot cookie sheet is also a crispier cookie. If you like your cookies thin and crispy try to cut down the amount of brown sugar in the recipe and replace it with white.

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Brown sugar does not attract the water from the butter as much since it already has it’s own moisture. This moisture also eventually turns into steam, which makes for taller, more cake like cookies. The brown sugar also gives the cookie a deeper caramel like flavor and helps the cookies to stay fresh tasting longer.

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Both sugars in some combination seem to work the best. You get the softness of the brown sugar cookie but the spread and crunch on the outer rims of the white sugar cookie.

Now let’s talk a little bit about leaveners.

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Baking soda is great and your cookies will most likely call for either only baking soda or a mixture of soda and baking powder. Baking soda is a base and it works the minute it comes into contact with an acid so if you are using only baking soda you will want to bake your cookies immediately.  You will also need some type of acid (think yogurt, vinegar, baking powder, buttermilk, etc) in your cookies to activate baking soda. Cookies made only with baking soda are crunchier and flatter, with cracked tops.

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Baking powder however is an acid on it’s own. If you have double acting baking powder your cookies will benefit from two different rises. The first is a reaction between the baking powder and the moisture in the cookie. The second is a reaction of the powder to the heat, giving it a second rise in the oven. Cookies with higher amounts of baking powder than baking soda create taller, cakier cookies with smoother tops.

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Chilling the dough overnight absolutely gives you a leg up on the competition. The resting period allows the moisture in the butter to soak into the flour completely. This helps to spread all of the flavors, in essence deepening the true cookie flavor. No matter what you do, if you want perfect cookies, chill your dough overnight.

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A combination of baking soda and baking powder is ideal as the baking soda will react off of the baking powder.

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Melted butter cookies must be chilled. When chilled for four hours they come out like this. Melted butter cookies are flatter and crisper than other cookies. This is due to moisture loss that occurs when you melt butter. The butter breaks down and spreads a lot faster after you’ve melted it. The faster a cookie spreads the crisper it will get as the cookie has a chance to spread a thin layer on still hot cookie tray. Melted butter cookies come out the crunchiest, but I found the flavor to be heavier than I like.

No matter how you like them here are some tips to better chocolate chip cookies;

Rest the dough overnight! But we already went over this.

Use the nicest quality chocolate you can comfortable afford. The butter flavor gets lost easily in chocolate chippers but the chocolate stands out, so use the best you can.

Use at least two different types of chocolate! Preferably in different sizes, like small chips and large chunks. This means each and every bite of each cookie will be different, new, and exciting!

Cut the salt in half and sprinkle some on the top of the cookie. The salt on the outside will help your tongue create more saliva, which helps to spread the flavor of the cookies over all of your cookie hungry tongue.

If your cookies are spreading out too much try adding a couple tablespoons of flour to help combat that and bake only a couple at a time until they no longer spread too much.

Basic Chocolate Chip Cookie Recipe (feel free to personalize!)

1 cup butter, softened at room temperature

1 cup white sugar

1 cup brown sugar

2 eggs

1 tablespoon vanilla extract

1/4 teaspoon salt, plus more for sprinkling on the cookies

3 1/4 cups all purpose flour

1 teaspoon baking soda

1 teaspoon baking powder

1 cup chopped dark chocolate pieces

1 cup milk chocolate chips

  1. In a large bowl or using a stand mixer cream together the butter and sugars on medium speed. Make sure to scrape down the sides of the bowl so that everything is combined.
  2. Turn the mixer onto high and slowly add in the eggs and vanilla extract.
  3. Stop the mixer and scrape down the sides again. Add the remaining ingredients and mix on low speed until just combined.
  4. Rest the dough in the fridge over night. When ready to bake preheat oven to 365°F. Scoop out the cookies and do not flatten them. Lightly sprinkle them with salt. Bake on a parchment lined cookie tray until the middles look underdone but the edges are browned, about 12-14 minutes for an average sized cookie.