A jam tart, or Crostata di Marmellata, is a favorite and justly famous dessert in the Mugello, and can be enjoyed in many welcoming trattorias in Scarperia, Borgo San Lorenzo, Marradi and other nearby towns. The fruits grown in the orchards and verdant valleys of the Mugello make wonderful jams and preserves, thus their popularity in this simple but rich Tuscan dolce. The crust for our crostata is a rich, shortbread one, and not the flaky crust that many are used to in the USA. You can make this crostata look a bit more elegant by baking it in a round, fluted tart pan with a removable bottom, or you can do as we sometimes do, and just lay out a round shape on a cookie sheet, crimping the edges in order to form a bit of a wall to hold the jam in.
For the crust:
2 1/2 cups all-purpose flour
10 Tablespoons chilled, unsalted butter
1/2 cup sugar
3 egg yolks
1/4 teaspoon salt
1/4 teaspoon baking soda
Grated rind of 1 lemon
For the filling:
2 1/2 cups high-quality fruit jam, such as plum, strawberry, or raspberry
Juice of 1/2 fresh lemon
To make the crust, cut the chilled butter into the sifted flour until the mixture resembles coarse breadcrumbs. Add all the other ingredients and quickly work them into a smooth dough. A food processor can be used for the entire process, and is really best because too much handling can make the dough tough. Divide the dough into two parts: one-third and two-thirds, shaping these into discs and wrapping them in plastic wrap. Chill the discs for at least one hour.
Roll the larger disc into a circle, and place in a 9-inch tart pan or on a cookie sheet. If using a cookie sheet, be sure to build a wall of the crimped edge.
Pour the jam, mixed with the lemon juice, into the shell. Roll out the second, smaller, piece of dough and cut into strips to make a lattice pattern over the top of the jam. Brush with cream or an egg wash, and bake at 375 degrees for about 20 minutes. This crust and the jam can overcook quickly, so do not exceed 30 minutes of baking time, and be sure to check for a golden color on the crust at 20 minutes. If the color is right, it is done! Enjoy!