01 -
Cream softened butter and sugar until light and fluffy, about 2 to 3 minutes. Add egg yolks and vanilla extract; mix until just combined. Gradually incorporate flour and salt on low speed until a soft dough forms, taking care not to overmix.
02 -
Scoop approximately 1 tablespoon of dough per cookie and roll into smooth balls. Arrange on a parchment-lined baking sheet, spacing 2 inches apart. Using your thumb or the back of a teaspoon, press a well into the center of each ball. Chill the tray in the refrigerator for 30 minutes to firm the dough.
03 -
Preheat oven to 350°F (175°C). Bake cookies for 14 to 16 minutes, until edges are lightly golden. If wells puff during baking, gently re-press with a teaspoon while still warm. Allow cookies to cool completely on a wire rack.
04 -
In a heavy-bottomed saucepan over medium heat, melt sugar while stirring continuously until deep amber in color. Immediately whisk in butter until fully incorporated. Remove from heat and gradually whisk in room-temperature heavy cream until smooth. Return briefly to low heat if necessary. Stir in flaky sea salt and let caramel cool until thick but pourable.
05 -
Spoon or pipe the cooled caramel generously into the cooled cookie wells, avoiding overflow. Allow caramel to set at room temperature or refrigerate briefly before serving for a cleaner presentation.