I'm a professional baker. Here are 9 staple ingredients I recommend stocking up on at Costco.

Most of my baked goods, especially holiday cookies, start with several sticks of butter.

I always use unsalted butter for baking, and I can grab a big package at Costco for less money than if I bought smaller ones at the grocery store.

A pack of Kirkland's unsalted butter comes with four 1-pound boxes and costs $13.99.

Pumpkin pie, bread, and cookies are always on the menu this time of year.

I love buying pureed pumpkin at Costco since I can get three 29-ounce cans for $8.99.

A baking staple, flour affects the consistency and texture of cookies, pie crusts, cakes, and more.

I prefer to use unbleached flour, and I can grab a pack of two organic, 10-pound bags for $15.79.

Sugar is a common sweetener that can also affect the texture of your baked goods, like when creamed with butter. 

Costco sells a 10-pound bag of C&H's granulated sugar for $7.99.

From making mini pecan pies to adding nuts to cookies, the cost of this ingredient can add up so I always snag a bag at Costco to take advantage of the wholesale price. 

A 2-pound bag of Kirkland's pecan halves sells for $14.99.

I wholeheartedly believe pure vanilla extract makes every baked good taste better.

People often opt for the artificial stuff since it's cheaper, but the pure ingredient is a great deal at Costco.

Stock up on a 16-ounce bottle of pure vanilla extract for just $11.99.

Brown sugar is the key to great flavor and a chewy texture in many cookie recipes. 

I often combine it with granulated sugar to make the perfect chocolate-chip cookies, sometimes swapping out the chocolaty chunks for holiday-colored M&M's.

A 7 1/2-pound bag of organic brown sugar is $8.99.

You can't make chocolate-chip cookies without this key ingredient.

I also will melt it and dip cookies, pretzel rods, and marshmallows in it for a fun, flavorful twist. 

A 4 1/2-pound bag of Kirkland's semisweet chocolate chips costs $9.99.

Powdered sugar looks a lot like snow, so I roll snowball cookies in it.

The ingredient is also great for making chocolate crinkle cookies and upgrading peanut-butter balls. 

A 7-pound bag of C&H's powdered sugar is $7.29.

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