The crust of the tart is made of what I call my Version 1 of pasta frolla (Italian tart dough).
- 1/2 cup minus 1 tablespoon [85 g, 3 oz.] superfine sugar (see Note 1 below) or a scant 3/4 cup of powdered sugar
- 1 and 3/4 cup [230 g, 8 1/4 oz.] unbleached all-purpose flour (plus as needed to flour the working surface) or 1/2 cup [65 g. 2 1/4 oz.] whole-wheat pastry flour and the rest all-purpose flour
- a pinch of salt
- 1 stick [8 tablespoons / 4 oz. / 113 g] cold unsalted butter, cut into small pieces
- grated zest of half a lemon
- 1 large egg and 1 large egg yolk, lightly beaten in a small bowl
- 1 and 3/4 cups [415 ml] of jam or fruit preserves, whatever flavor you like (Note: I use my homemade fruit preserves, which have a low sugar content. I recommend you choose a good quality product, made with mostly fruit.)
Note 1: Superfine sugar is also referred to as baker's sugar. It’s available in most supermarkets. If you cannot find “superfine” sugar, you can make your own by putting some regular granulated sugar in a food processor or blender and letting it run until the sugar is finely ground. The finer the sugar, the better for this recipe, so avoid unrefined sugar, which is coarse-grained.
Note 2: The less gluten in the flour, the better. Do not use bread flour. On the other hand, if you have access to pastry flour, try using it instead of some of the all-purpose flour.
To bake the tart, use a 9 or 9.5-inch [23-24 cm] fluted round tart pan with removable bottom, about 1 inch [2.5 cm] high. (See Note 3 at the end on using a different pan.)
Making pasta frolla with a food processor:
- Put sugar, flour, salt, and lemon zest in the food processor and pulse a few times to mix.
- Add butter and pulse a few times, until the mixture has the consistency of coarse meal.
- Empty food processor's bowl onto your work surface.
- Make a well in the center of the mounded flour and butter mixture and pour the beaten eggs into it (reserve a teaspoon of the egg mixture for glazing purposes later on: place it in the refrigerator, covered, until ready to use).
- Add the lemon zest to your flour/butter/egg mixture.
- Use a fork to incorporate the liquid into the solid ingredients, and then use your fingertips.
- Knead lightly just until the dough comes together into a ball.
- Shape the dough into a flat ellipse 1 inch / 2.5 cm thick and wrap in plastic wrap. Place the dough in the refrigerator and chill for at least two hours. You can refrigerate the dough overnight.
Assembling and baking the crostata:
- Preheat the oven to 375 F [190 C].
- Take the pasta frolla out of the fridge, unwrap it and cut away 1/4 of the dough. Reserve this dough to make the lattice top of the crostata. Refrigerate this dough while you work on the tart base.
- To help roll the crostata dough, keep the dough on top of the plastic wrap that you had it wrapped in. This can help rolling the dough and can also help when transferring the dough to your pan. You can also use parchment paper for this. However, you can also roll the dough directly on a work surface if you prefer.
- Lightly dust the top of the dough and your work surface with flour. Keep some flour handy to dust the dough as you go along.
- If the dough is very firm, start by pressing the dough with the rolling pin from the middle to each end, moving the rolling pin by a pin's width each time; turn the dough 90 degrees and repeat; when it softens, start rolling.
- Roll the dough into a circle about 1/8 inch (3 mm) thick.
- If you used the plastic wrap as rolling surface, flip dough over the pan, centering it, and delicately press it all around so the corners are well covered. Peel away the plastic wrap.
- Trim the excess dough hanging over the edges of the pan. Press the remaining dough around the border into the sides of the pan making sure the border is an even thickness all the way around.
- Add a drop or two of water to the beaten egg and with a pastry brush, lightly glaze the surface of the bottom of the shell. Make sure you still have some egg wash to glaze the decoration. (Note: this is something I have started to do only recently, after reading about it. The idea is to create a thin layer between the filling and the shell that keeps the latter crisper.)
- Prick the shell with a fork in several places. Refrigerate the rolled shell while you work on the decoration.
- Take out of the fridge the reserved pasta frolla you had cut away earlier. Roll it with your pin and cut into strips or use cookie cutters to make small shapes (this is not traditional, but it looks cute); or roll with your hands into thin ropes.
- Take out the shell from the fridge and spread the jam or fruit preserves evenly over it.
- Use the prepared strips or rolls of dough to make a lattice over the surface, or decorate with the cut shapes. (Note: set aside dough scraps to make frollini)
- Use the remaining egg wash to glaze the border and strips of dough, again using a pastry brush.
- Put the tart in the oven and bake for 25 minutes.
- After 25 minutes, check the tart to estimate the time remaining, and continue baking until the tart is of a nice golden hue. (Note: Every oven is different. In my oven it takes 34 minutes to bake the tart until golden.)
- When done, remove the tart from the oven and let cool. If you have used a tart pan with a removable bottom, then release the tart base from the fluted tart ring. Make sure the tart is completely cool before slicing and serving.
Note 3: If you don't have a fluted round tart pan with removable bottom, you can use a cake pan of the same size, or a pie plate. I used my 9-inch cake pan, which is 9 inches [23 cm] wide and 1.5 [a bit less than 4 cm] inches high to make a crostata di marmellata. Making the border required a bit more dexterity since you want it to be lower than the rim of the pan. The crostata was ready a few minutes earlier than when I use the tart pan. I also used a 9.5 inches [24 cm] Pyrex pie plate to make a crostata di marmellata. The baking time in this case was the same as the one noted in the recipe above. The plate is 1.75 inches [4.5 cm] so the same note about the border applied. You can also use a fluted rectangular tart pan with removable bottom to make crostata.