Dulce de Leche Cookies

1 1/2 cups flour
3/4 cup quality Dutch-process unsweetened cocoa
3/4 teaspoons ground cinnamon
1/2 teaspoons cayenne
1/4 teaspoon salt
1/4 tsp freshly ground black pepper
1 cup sugar
1 1/2 teaspoons vanilla extract
1 egg
12 tablespoons cold unsalted butter, cut into small pieces

Whisk the flour, cocoa, cinnamon, cayenne, salt, and pepper together in a medium bowl and set aside.

Put sugar, vanilla, and egg into a large bowl and beat with an electric mixer on high speed until thick and pale, about three minutes. Add butter and continue to beat on high speed until smooth, about three minutes more. Using your fingers work flour mixture into butter mixture until dough is just combined. Divide dough in half and roll each half into a 9-inch log. Wrap each log in parchment paper, twisting ends tightly to make a uniform cylinder. Freeze dough logs for at least eight hours and as long as overnight.

Preheat oven to 350˚ F. Unwrap dough and slice each log into rounds 1/3-inch thick. Place rounds one inch apart on parchment paper-lined cookie sheets. Bake cookies until slightly puffed and tiny cracks appear on surface, about eight minutes. Transfer cookies to a rack to let cool. Makes about four dozen cookies.

To make the dulce de leche cookies, follow recipe as above, but instead of freezing dough, chill in refrigerator. Slice rounds as directed, but flatten rounds and scoop a generous 1/4 teaspoonful (which is really about a half teaspoon) ball of dulce de leche in the middle of one round. Lay a second round over dulce de leche, pinching edges tightly and smoothing out and rolling gently between balls to make a smooth mound. Bake for 9 minutes.