LYDIA'S AUSTRIAN RASPBERRY SHORTBREAD

Steps:

• Cream the butter in a mixer fitted with a paddle attachment (or using a hand mixer) until soft and fluffy. Add the egg yolks and mix well.
• Mix the granulated sugar, flour, baking powder, and salt together. Add to the butter and egg yolk mixture and mix just until incorporated and the dough starts to come together. Turn the dough out onto a floured work surface and form into two balls. Wrap each ball in plastic wrap and freeze at least 2 hours or overnight (or as long as a month, if you like).
• Heat the oven to 350 degrees.
• Remove one ball of dough from the freezer and coarsely grate it by hand or with the grating disk in a food processor into the bottom of a 9x13-inch baking pan or a 10-inch tart pan with a removable bottom. Make sure the surface is covered evenly with shreds of dough.
• With the back of a spoon or a flexible spatula, spread the jam over the surface, to within 1/2 inch of the edge all the way around. Remove the remaining dough from the freezer and coarsely grate it over the entire surface.
• Bake until lightly golden brown, 30 to 40 minutes. As soon as the shortbread comes out of the oven, dust with confectioners' sugar. Cool on a wire rack, then cut in the pan with a serrated knife.