Chocolate Caramel Thumbprints

Whisk together the flour, cocoa, and salt in a bowl.

Using an electric mixer, beat the butter in a large bowl until creamy. Add the sugar and beat well until fluffy. Beat in the whole egg and egg yolk. Mix in the vanilla. With the beaters on low speed, mix in the flour mixture just until incorporated and the dough comes together. Gather the dough into a ball, then divide it in half. Wrap each half separately in plastic wrap and refrigerate until firm, about 1 hour.

Preheat the oven to 350°F (175°C). Line 2 baking sheets with parchment paper.

Working with 1 portion of the dough at a time, roll it into 1-inch balls and arrange them about 2 inches apart on the prepared sheets. Make an indentation in the center of each ball using the handle end of a wooden spoon or your thumb, being careful not to go all the way through the dough.

Bake for about 13 minutes, rotating the sheets from top to bottom and front to back about halfway through baking, or until the cookies feel just slightly firm. Transfer the cookie sheets to a rack and immediately depress the centers of the cookies again using the handle end of a wooden spoon to reinforce and widen the indentation to about 3/4 inch in diameter. Transfer the cookies to a rack to cool completely.

Heat the caramels and cream in a medium saucepan over moderately low heat, stirring often, until the caramels are melted and the mixture is smooth, about 5 minutes. Using the smallest, pointiest spoon you have, such as a demitasse spoon, spoon the caramel into the indentations in the cookies, filling just up to the rim. If the caramel becomes too thick, place the saucepan back over low heat for a few seconds. Let the caramel set before drizzling the cookies with chocolate.

Melt the chocolate in a microwave-safe bowl in the microwave for 20- to 30-second intervals on medium power, stirring after each interval, until melted and smooth. Let cool at room temperature for a few minutes.

Place the cookies close together, but not touching, on racks set over wax paper. Pour the chocolate into a small plastic bag (or squeeze bottle). Seal the bag and make a tiny cut in one corner. Working quickly, drizzle the chocolate in a zigzag pattern over the cookies. Let the chocolate set completely. (You can store the cookies, layered between sheets of wax paper, in an airtight container at room temperature for up to 4 days or in the refrigerator for up to 2 weeks.)