Salty Chocolate Chunk Cookies

INGREDIENTS

• 3/4 cup (packed) light brown sugar
• 2 large egg yolks
• 1/2 cup (1 stick) unsalted butter, room temperature
• 1/2 cup sugar
• 8 ounces semisweet or bittersweet chocolate (do not exceed 72% cacao), coarsely chopped
• 1/2 teaspoon kosher salt
• 1 teaspoon vanilla extract
• 1/4 cup powdered sugar
• Maldon or other flaky sea salt
• 1/4 teaspoon baking soda
• 1 1/2 cups all-purpose flour
• 1 teaspoon baking powder
• 1 large egg