7tablespoonssalted butter plus another ½ tablespoon for the pan.
¼cupsugar(90 grams)
½teaspoongrated lemon zest
1largeegg yolk
Instructions
In a large bowl, whisk together the flour, baking powder, salt and cardamom.
With an electric mixer, preferably a stand mixer with paddle attached, beat 7 tablespoons of the butter until light and fluffy. Add the sugar and lemon zest and continue beating for another 2 minutes. stopping to scrape bowl as needed.
Reduce the speed to low and add the egg yolk, beating just until blended.
Add the flour mixture and stir with the paddle attachment just until a dough forms. You can also do this step by hand or carefully with the very lowest speed of a handheld mixer. If using a handheld, be careful not to overbeat the dough.
Scrape the dough onto a piece of plastic wrap and shape into a log. Wrap tightly and freeze for 30 minutes.
Preheat the oven to 350°F. Line the inside of a loaf pan with foil leaving an overhang for lifing. Rub the reserved softened ½ tablespoon butter across the bottom and about 1 inch up the sides.
Using the large holes on a grater, grate half the dough into the pan. Do not press down. Put the pan with the grated dough back in the freezer for about 5 minutes while you get the jam ready.
Using the back of a large spoon, spread the jam or preserves over the grated dough, then grate remaining dough over the jam. You will pile it pretty high, but it will bake down quite a bit.
Bake until the top is golden brown, about 35 to 40 minutes. Let cool completely, then lift from pan and cut into squares.