The Linzer tart is a famous walnut and jam pastry from Austria. Here the classic combo is simplified into a delicate and delicious cookie. The recipe calls for raspberry, but you can use any kind of jam. Look for the sparkling sugar with the cake decorations in the baking section of the market. This recipe comes from Diamond of California®.
Cookies can be made up to 3 days ahead; store in an airtight container.
Preheat the oven to 350 degrees F. Line 2 large, heavy baking sheets with parchment paper.
Using an electric mixer, beat the butter and the sugar until light and fluffy. Beat in the egg yolks. Gradually mix in the flour, baking powder, and salt. Mix in the walnuts.
Roll the dough into 1-inch balls, about 2 level tablespoons each. Roll the balls in the additional chopped walnuts or the sparkling sugar to coat. Arrange the dough on the prepared baking sheet, spacing evenly. Using your thumb, make a deep indentation in the center of each cookie. Spoon a level teaspoonful of preserves into each indentation. Bake the cookies until golden brown, about 12 minutes.