These cookies come to us from Carley McKee. She says, “For me, thumbprint cookies are as classic as eggnog and nutmeg. Sometimes fancy, decorated sugar cookies and gingerbread men outshine the thumbprint on those platters you bring over to your neighbors each year. But underneath those flashy cookies lies the thumbprint. It has the delicate flavor of a linzer tart but the humble presentation of something less formal and far more familiar.”
1 stick (4 ounces) unsalted butter, softened
¼ cup granulated sugar
1 large egg, separated
½ teaspoon vanilla extract
1 cup all-purpose flour
¾ cup walnuts
About ½ cup of whatever jam you like (Carley likes strawberry-ginger)
Preheat oven to 350°F. Beat butter and sugar in a medium bowl until light and creamy. Beat yolk and vanilla into the butter and sugar mixture until smooth.
In a separate bowl combine flour and salt. Add dry ingredients to wet and beat until combined. Don’t over mix. Dough should be light and grainy.
Shape dough into 1-inch balls and place on a baking sheet lined with parchment paper, leaving about 1½ inches between them. Use your thumb and squish the center of each ball, leaving a small crater in the middle. Place baking sheet in the refrigerator to chill for at least 30 minutes.
Meanwhile, spread walnuts out on a parchment-lined baking sheet. Place in preheated oven and let toast for 8–10 minutes. Nuts are done when lightly browned and super fragrant. Be sure to check them often to prevent burning; it happens fast!
Pulse nuts in food processor until they create a nice uniform crumb.
Dump nuts onto a small plate.
Take dough out of fridge. Dip each cookie into the reserved egg whites and then roll in chopped walnuts, making sure to get a good thick crumb coat on the top and sides without filling the crater.
Place cookies back on parchment lined baking sheet and fill the crater of each cookie with jam. You can use whatever type of jam or preserve you like.
Place baking sheet in 350°F oven and bake for 12–15 minutes, or until cookie sets and nuts are well toasted. Let cool and enjoy!