First Step: Brown ¾ cup of the unsalted butter over medium heat until it turns a light amber color with a nutty aroma, then transfer it to a heatproof bowl, leaving the darker bits behind, and chill for 10-15 minutes.

Second Step: Combine the browned butter with the remaining softened unsalted butter to total 1 cup, then beat this mixture with the light brown sugar until it’s creamy.

Third Step: Mix in the 2 egg yolks and 1 teaspoon of vanilla extract until well incorporated.

Fourth Step: Sift in the 2 ¼ cups of all-purpose flour and ¼ teaspoon of salt, stirring until the dough forms.

Fifth Step: Shape the dough into 1-tablespoon balls and place them on the lined baking sheets.

Sixth Step: Bake at 350°F for 10-12 minutes until the edges are lightly browned.

Seventh Step: Immediately press indentations in the centers of the cookies while they’re still warm, then let them cool on a wire rack.

Eighth Step: Fill the indentations with the dulce de leche and sprinkle with flaked sea salt.