Brown Butter Chocolate Chip Cookies

Method

1. Melt the butter in a light-colored saucepan over medium heat, swirling as it foams. After 5 to 7 minutes the foam clears, the solids on the bottom turn amber and it smells like toasted hazelnuts, so pour it all into a heatproof bowl and cool 15 minutes.
2. Whisk both sugars and the kosher salt into the butter, then the egg, yolk, milk and vanilla until glossy. Add the flour and baking soda and fold until the last streaks vanish, then fold in the chocolate.
3. Cover and chill the dough at least 1 hour (up to 2 days) until firm enough to scoop; the chill is not counted in the recipe time.
4. Heat the oven to 375°F and line two sheet pans with parchment. Scoop 2-tablespoon mounds, about 45 g each (about 2 dozen cookies; a serving is 2), 2 inches apart.
5. Bake one pan at a time on the middle rack 10 to 12 minutes, until the edges are set and golden and the centers still look soft. Sprinkle with flaky salt, rest on the pan 5 minutes, then move to a rack.

Food safety. Do not eat the raw dough; it contains raw egg and uncooked flour.