1 cup all-purpose flour
1/3 cup cocoa powder
1/4 teaspoon salt
8 tablespoons butter, softened
2/3 cup sugar
1 large egg, separated, plus 1 egg white
2 tablespoons milk
1 teaspoon vanilla extract
1 cup chopped pecans, chopped fine
14 soft caramel candies
3 tablespoons heavy cream
Adjust oven rack to upper-middle and lower-middle positions and heat oven to 350 degrees. Combine flour, cocoa, and salt in small bowl. With electric mixer on medium-high speed, beat butter and sugar until fluffy, about 2 minutes. Add egg yolk, milk, and vanilla and mix until incorporated. Reduce speed to low and add flour mixture until just combined. Refrigerate dough until firm, at least 1 hour.
Whisk egg white(s) with fork or whisk in another bowl until frothy. Place pecans in another bowl. One at a time, roll dough into 1-inch balls, dip in egg whites, letting excess drip off, then roll in pecans. Place balls 1 inch apart on lightly greased baking sheets. Using teaspoon measure or your finger, make indentation in center of each ball.
Bake until set, 10 to12 minutes, switching and rotating sheets halfway through baking.
Meanwhile, microwave caramels and cream in bowl, stirring occasionally, until smooth, 1 to 2 minutes. Once cookies are removed from oven, gently press existing indentations with teaspoon measure. Fill each with 1/2 to 1 teaspoon caramel mixture. Cool 5 minutes, then transfer to wire rack and cool completely.
Adapted from Cookscountry.com