Ingredients

• 8 ounce unsalted butter
• 0.75 cup light brown sugar, packed
• 0.25 cup granulated sugar
• 1 large egg
• 1.5 teaspoon vanilla extract
• 1.75 cup gluten-free all-purpose flour
• 0.25 teaspoon xanthan gum
• 1 teaspoon baking soda
• 1 teaspoon kosher salt
• 6 ounce dark chocolate chips
• 0.5 teaspoon fleur de sel

Steps

1. Preheat oven to 350°F. Line two baking sheets with parchment paper.
2. Place 8 ounces unsalted butter in a saucepan over medium heat. Swirl occasionally (do not stir) as the butter melts, foams, and the milk solids turn golden brown, about 5 to 7 minutes. Watch carefully to avoid burning—the butter should smell nutty and aromatic.
3. Pour the browned butter (including all the browned solids at the bottom) into a small bowl. Set aside to cool for 2 minutes.
4. In a large mixing bowl, whisk together the cooled brown butter, 3/4 cup packed brown sugar, and 1/4 cup granulated sugar until combined.
5. Whisk in 1 large egg and 1 1/2 teaspoons vanilla extract until smooth.
6. In a separate small bowl, whisk together 1 3/4 cups gluten-free all-purpose flour, 1/4 teaspoon xanthan gum, 1 teaspoon baking soda, and 1 teaspoon kosher salt.
7. Fold the dry ingredients into the wet ingredients using a spatula or whisk until just combined; do not overmix. The dough should be slightly thick and cohesive.
8. Fold in 6 ounces dark chocolate chips until evenly distributed throughout the dough.
9. Using a cookie scoop or rounded tablespoon, drop dough onto prepared baking sheets, spacing them about 2 inches apart. You should have approximately 24 cookies.
10. Bake for 12 to 14 minutes, until the edges are golden brown but the centers still look slightly underbaked. The cookies will continue to cook on the hot pan after removal from the oven.
11. Remove baking sheets from the oven and sprinkle each warm cookie with a pinch of fleur de sel (about 1/4 teaspoon total distributed across all 24 cookies).
12. Let cookies cool on the baking sheet for 5 minutes, then transfer to a wire rack to cool completely. They will firm up as they cool.