These luscious buttery, walnut-covered thumbprint cookies are delicious ice-breakers at any party. You can easily pipe or spoon the rum-flavored eggnog filling into the center of each cookie.
Cream softened butter using an electric mixer on medium-high speed for about 1 minute. Then add sugar and nutmeg and beat until well combined.
Beat in egg yolks and vanilla until combined.
Gradually add flour. Cover and chill dough until it is easy to handle.
When you are ready to bake, preheat oven to 375 degrees F., and line cookie sheets with parchment paper.
Shape dough into 1-inch balls. Roll each first in egg white, then in chopped walnuts to coat.
Place them on prepared cookie sheets, about 1-inch apart. Press your thumb into the center of each ball to form a well.
Bake for 10 minutes or until edges are lightly browned. Carefully transfer cookies to wire racks to cool completely.
While cookies are cooling, cream ¼ cup or ½ stick of softened butter for about 1 minute. Then add 1 cup of sifted confectioners’ sugar and continue creaming until fluffy. Beat in 1 teaspoon rum (more or less, if necessary) to make a spreading consistency.
Just before serving, either pipe or spoon enough rum filling into the center of each to make irresistible eggnog thumbprint cookies.
Place them on prepared cookie sheets, about 1-inch apart. Press your thumb into the center of each ball to form a well.
