1-First Step: Get your oven and baking sheet ready Start by preheating your oven to 400°F. This higher temperature helps the cookies bake quickly, which keeps the centers soft while the edges turn lightly golden. Line a baking sheet with parchment paper so the cookies do not stick and cleanup stays easy. Before you begin mixing, measure all ingredients so everything is ready to go. Since this recipe moves fast, it helps to have the butter cubed, the eggs at the ready, and the chocolate chips and walnuts nearby. If you like extra-thick cookies, you can also chill the dough later after portioning.

2-Second Step: Cream the butter and sugars Add the 1 cup cold salted butter, 1/2 cup dark brown sugar, 1/2 cup light brown sugar, and 1/2 cup granulated sugar to a stand mixer. Mix on low for about 30 seconds so the ingredients begin to come together without flying out of the bowl. Then switch to medium speed and mix for about 4 minutes until the mixture looks fluffy and lighter in color. This step builds the base of the cookie and helps create a soft texture. If the butter seems too cold at first, keep mixing. The texture should become creamy and smooth by the end. For the thickest cookies, use cold butter just as written in the recipe.

3-Third Step: Add the wet ingredients and dry flavor boosters Crack in the 2 eggs, then add the 2 teaspoons vanilla, 1 teaspoon kosher salt, 1 teaspoon baking soda, and 2 teaspoons cornstarch. Mix for about 1 minute until the dough looks smooth. The eggs help hold everything together, while the cornstarch gives the cookies a soft, thick bite. At this stage, the dough should smell sweet and buttery. If you are making chocolate chip walnut cookies for someone with a preference for less salt, you can reduce the kosher salt slightly, but the recipe is balanced as written. The salt helps highlight the chocolate and walnut flavor.

4-Fourth Step: Mix in the flour Turn the mixer to low and add the 3 cups all-purpose flour slowly. Mix only until the flour is just combined. Overmixing can make the cookies tough, so stop as soon as you no longer see dry flour in the bowl. If the dough looks a little loose, add a bit more flour, one tablespoon at a time. This is a useful checkpoint for anyone baking at home. Different flour brands and humidity levels can affect dough texture, so a tiny flour adjustment is normal. You want a dough that holds its shape but still feels soft and scoopable.

5-Fifth Step: Stir in the chocolate chips and walnuts Fold in the 2 1/2 cups chocolate chips and 1 1/2 cups chopped walnuts. You can use the mixer on low for just a few seconds or stir them in by hand with a sturdy spoon. Make sure the chips and nuts are spread throughout the dough so each cookie bakes with a nice mix of flavors and textures. If you want to try a variation, this is the point where you can swap the walnuts for pecans, pistachios, peanuts, or macadamias. That keeps the same cookie base while giving you a different flavor profile. It is a fun way to make these chocolate walnut cookies your own.

6-Sixth Step: Scoop and space the dough Use a cookie scoop or spoon to portion the dough into 3-tablespoon mounds. Place them on the prepared baking sheet about 2 inches apart. This spacing gives the cookies room to spread without running into each other. You should get large bakery-style cookies that bake evenly and stay thick. If you want to freeze some dough for later, this is the best stage to do it. Flash freeze the scoops on a tray until firm, then move them to a freezer bag. That makes it easy to bake just a few cookies whenever a craving hits.

7-Seventh Step: Bake until just golden Bake the cookies for 8 to 9 minutes, or until the edges and tops look lightly golden. The centers may still look a little soft, and that is exactly what you want. They will finish setting as they cool on the pan. If your oven runs hot, check them at the 8-minute mark. For softer cookies with less spreading, stick close to the 400°F temperature. That heat works well with the cold butter and cornstarch to create thick, chewy results.

8-Eighth Step: Cool before moving Let the cookies rest on the baking sheet for 2 to 3 minutes. This short rest helps them firm up so they do not break when moved. After that, transfer them to a wire rack to cool fully. Cooling on the rack keeps the bottoms from getting soggy and helps the texture stay just right. If you like warm cookies, enjoy one while it is still slightly soft in the center. That fresh-from-the-oven bite is hard to beat!