Cheesecake Thumbprints

Directions

1. 1
   In the bowl of an electric mixer fitted with the paddle attachment, beat cream cheese on medium speed until light and fluffy, about 3 minutes, scraping down the sides of the bowl as needed.
2. 2
   Add 1/4 cup sugar and a pinch of salt, and beat until smooth, about 3 minutes.
3. 3
   Add 1 egg yolk, sour cream, and vanilla; beat until smooth.
4. 4
   Transfer to a small bowl, and refrigerate for about 30 minutes.
5. 5
   Preheat the oven to 350F, with racks in the upper and lower thirds.
6. 6
   Line two large baking sheets with parchment paper; set aside.
7. 7
   In the bowl of an electric mixer fitted with the paddle attachment, beat the butter and remaining 1/4 cup sugar on medium speed until well combined, 1 to 2 minutes, scraping down the sides of the bowl as needed.
8. 8
   Add remaining 1/4 teaspoon salt and egg yolk; beat to combine.
9. 9
   With mixer on low speed, gradually add the flour, mixing until just combined.
10. 10
    Shape level tablespoons of dough into balls, and place on prepared baking sheets about 1 inch apart.
11. 11
    Using the lightly floured end of a thick wooden spoon handle (or your thumb), make an indentation in the center of each ball.
12. 12
    Bake 10 minutes; remove from oven and make indentations again.
13. 13
    Rotate sheets, return to oven, and bake until edges of cookies begin to turn golden, 7 to 9 minutes more.
14. 14
    Transfer cookies to a wire rack to cool completely.
15. 15
    Using a small teaspoon, fill the center of each cookie with about 1 teaspoon creamcheese filling, mounding it slightly.
16. 16
    Return cookies to the oven, and bake until the filling is firm, 7 to 8 minutes.
17. 17
    Transfer cookies to a wire rack to cool completely.
18. 18
    Refrigerate in an airtight container, layered between waxed or parchment paper, at least 4 hours before serving (cookies can be refrigerated overnight).
19. 19
    In a heatproof bowl set over (but not touching) simmering water, melt 2 ounces semisweet chocolate; let cool.
20. 20
    Follow instructions for Cheesecake Thumbprints, adding melted chocolate to butter mixture along with the egg yolk and salt.
21. 21
    Reduce the flour by 3 tablespoons, and whisk with 3 tablespoons Dutch-process cocoa powder before adding to the dough.
22. 22
    (The edges of these cookies will be firm to the touch when baked)
23. 23
    The floured handle of a wooden spoon is pressed into each ball of cookie dough to make an indentation.
24. 24
    A rich cheesecake filling is added to the centers after the cookies are partially baked.