Gooey Cookie Recipe

Prepare dry ingredients

Whisk together the all-purpose flour, baking soda, salt, and cornstarch (cornstarch helps create a tender, slightly gooey interior) in a medium bowl. Set aside.

Cream butter and sugars

In a large bowl or stand mixer fitted with the paddle attachment, beat the softened unsalted butter, granulated sugar, and light brown sugar on medium speed until light and fluffy, about 2 to 3 minutes. Scrape down the bowl as needed.

Add eggs and vanilla

Add the whole egg and the extra egg yolk, one at a time, beating until incorporated. Mix in the vanilla extract. The additional yolk adds richness and chewiness that helps the cookie stay gooey.

Combine wet and dry

With the mixer on low speed, gradually add the flour mixture to the butter-sugar mixture, mixing just until combined and no dry streaks remain. Do not overmix.

Fold in chocolate

Fold in 1.5 cups semi-sweet chocolate chips and 1/2 cup dark chocolate chunks by hand so they are evenly distributed through the dough.

Prepare gooey filling

In a small bowl, stir together the sweetened condensed milk and 1 tablespoon melted butter until smooth. This will be a sticky, pourable goo that keeps the center melty after baking.

Form cookie balls with gooey center

Scoop about 3 tablespoons (roughly a large golf-ball-sized portion) of dough per cookie. Flatten each dough portion into a 3-inch disk, place about 1 teaspoon of the condensed milk mixture in the center, then fold dough around the filling and roll gently to reseal, forming a smooth ball. If desired, press a few extra chocolate chips or a dark chunk into the top so you get melty pockets. Repeat until all dough is used, leaving at least 2 inches between balls on the baking sheet.

Chill (optional but recommended)

For best shape and gooey texture, chill the assembled cookie balls on a baking sheet for 20–30 minutes. Chilling prevents excessive spread so the center stays gooey while the edges set.

Preheat oven

Preheat the oven to 350°F (175°C). Line two baking sheets with parchment paper or silicone baking mats.

Bake

Place chilled cookie balls on the prepared baking sheets about 2–3 inches apart. Bake one sheet at a time in the center of the oven for 10–12 minutes, or until the edges are lightly golden but the centers still look soft and slightly underbaked — this yields a gooey interior. Rotate the pan halfway through baking for even color.

Finish and cool

Remove cookies from oven and immediately, if desired, brush the tops lightly with the optional melted butter and sprinkle with coarse sugar and a pinch of flaky sea salt while still warm. Let cookies cool on the baking sheet for 8–10 minutes so they set slightly, then transfer to a wire rack to cool another 10 minutes. The center will remain soft and gooey; the cookies will firm as they cool but retain a rich, melty interior.