Melty Brown Butter Cookies

Step 1 -Line two baking sheets with parchment paper.

Step 2 -In a medium saucepan over medium heat, add the butter and heat, frequently swirling the saucepan and stirring, until it has melted.

Step 3 -Cook the melted butter until it turns golden-brown and smells nutty, about 5 minutes.

Step 4 -Pour the brown butter into a large bowl and let it cool.

Step 5 -In a medium bowl, add the flour, the baking soda, the fine sea salt, and the cinnamon and whisk to combine.

Step 6 -Add the brown sugar and the granulated sugar to the cooled brown butter and whisk until it is combined.

Step 7 -Add the egg, the egg yolk, and the vanilla extract to the brown butter mixture and whisk until it is well-combined.

Step 8 -Add the flour mixture to the brown butter mixture and gently stir until it is combined.

Step 9 -Add the chopped chocolate to the cookie dough.

Step 10 -Scoop the cookie dough into 1/4-cup-sized pieces and roll each of them into balls. There should be a total of about 16.

Step 11 -Evenly divide the dough balls between the prepared baking sheets.

Step 12 -Transfer the baking sheets to the refrigerator and let the dough balls chill for at least 1 hour and up to 24 hours.

Step 13 -Preheat the oven to 350 degrees F.

Step 14 -Bake the cookies until the edges turn golden, rotating both of the baking sheets halfway through, about 15 minutes.

Step 15 -Transfer the baking sheets from the oven and carefully tap them on the counter once to make the cookies flatter and chewier.

Step 16 -Place the baking sheets on a wire rack and evenly sprinkle each of the cookies with the flaky sea salt. Let them cool, about 5 minutes.

Step 17 -Transfer the cookies to the wire rack and let them cool completely.

Step 18 -Serve.