Ingredients (Serves 10-12)

For pasta frolla

• 1/3 cup / 65 g ultra-fine sugar or 1/2 cup powdered sugar (see Note 1)
• 1/2 cup / 60 g whole-wheat pastry flour
• 1/2 cup / 65 g unbleached all-purpose flour (see Note 2)
• 1/4 cup / 30 g almond flour or almond meal
• 1/4 cup / 30 g whole-grain barley flour OR unbleached all-purpose flour
• A pinch of salt
• 1/4 teaspoon grated zest of organic orange or lemon
• 6 tablespoons / 85 g / 3 ounces cold unsalted butter, cut into small pieces
• 1 large egg (possibly from pastured poultry), lightly whisked to blend yolk and white

For the filling

• 2 large egg (possibly from pastured poultry)
• 50 g ultra-fine OR granulated sugar
• 1/8 teaspoon Lebkuchen spices (see Note 3)
• 50 g golden brown sugar OR 50 g granulated sugar
• 1 tablespoon corn flour
• 225 ml / 1 cup minus 1 tablespoon cold water
• 1 1/2 tablespoons / 22.5 ml apple cider vinegar

Instructions

Note 1: Ultrafine or superfine sugar is also referred to as baker’s sugar. If you cannot find it, 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.

Note 2: The less gluten (as indicated by % protein) in the flour, the better (I like to use Perfect Pastry blend by King Arthur Flour). Do not use bread flour.

Note 3: Lebkuchengewürz is a spice mix used in Germany to make Lebkuchen. There are many versions of this mix, which contains mostly cinnamon and a variety of other spices. The one I use includes, besides cinnamon, coriander, star anise, orange and lemon zest, nutmeg, fennel, cloves and cardamom. You can substitute it with some pumpkin pie spice mix (cinnamon, allspice, nutmeg, ginger, mace and cloves) or a mix of cinnamon, ginger and a hint of nutmeg.

How to make the pasta frolla

Put sugar, flours (2nd through 5th ingredient n the list) and salt in the bowl of the food processor fitted with a steel blade and pulse a few times to mix.

Add butter and pulse a few times for 3 seconds until the mix resembles coarse meal. Empty food processor’s bowl onto your work surface.

[If you don’t have a food processor: Whisk together sugar, flours (2nd through 5th ingredient above) and salt in a bowl. Rub or cut the butter into the sugar and flour mixture until it has the consistency of coarse crumbs. You can do this in the bowl or on your work surface, using your fingertips or an implement of choice.]

Make a well in the center of the mounded flour and butter mixture and pour the egg and zest into it. Use a fork to incorporate the liquid into the solid ingredients, then use your fingertips.

Knead lightly just until the dough comes together into a ball. Use some all-purpose flour as needed to flour your hands to prevent excessive sticking.

Shape the dough into a flat disk 1 inch / 2.5 cm thick and wrap in plastic wrap. Place the dough in the refrigerator and chill for at least two hours. I usually make it the evening before and refrigerate it overnight.

How to prepare the bottom layer of the crostata

To bake the crostata, I recommend using a 9 or 9 1/2-inch / 23-24 cm fluted round tart pan with removable bottom, no less than 1 inch / 2.5 cm high.

Take the pasta frolla out of the fridge and unwrap it. I recommend you roll the dough on a piece of parchment paper or the plastic film in which it was wrapped as it is quite crumbly.

Lightly dust with flour the top of the dough and the surface on which you are rolling it. Keep some flour handy to lightly 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 gently.

Roll the dough into a circle about 1/8 inch / 3 mm thick. If you used parchment paper or plastic wrap as rolling surface, flip the dough over the tart pan, centering it, and delicately press it all around so the corners are well covered. Peel away the wrap.

Trim the excess dough hanging over the edges of the pan and use it, as necessary, where you find that you came up short. Make sure the dough comes well up to the edge all around and even a bit higher, as the filling is liquid when poured into the baked shell and it will fill it to the brim.

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. Prick the shell with a fork in several places. Refrigerate while you prepare the oven.

How to blind-bake the shell

Heat the oven to 350 F / 177 C.

Take the unbaked shell out of the refrigerator. Line it with a piece of parchment paper or foil and fill with pie weights.

Bake the shell for 20 minutes, then take it out and remove the parchment paper with the pie weights. Bake for another 10 minutes, then take out of the oven and set aside.

While the shell bakes, prepare the filling.

How to make the filling

Whisk eggs and first amount of sugar in a bowl until bubbly. Sprinkle spices and whisk briefly to incorporate them.

Whisk together corn flour and second amount of sugar in a saucepan, then whisk in water and vinegar. Bring to a boil, whisking until sugar is dissolved. Remove pan from heat. Add liquid to the egg mixture in a slow stream, whisking constantly.

Pour filling into the saucepan and cook over low heat, stirring constantly with a wooden spoon, until it reaches 175 F /80 C or coats the back of the spoon (the line stays clear when you draw your finger across). Do not let the filling boil. Place the saucepan into a cold water bath and stir briefly. Take saucepan out of the cold water bath. If the shell is not yet ready, cover the surface of the filling with a piece of wax paper.

How to fill and bake the tart

Make sure the oven is at 350 F / 177 C.

Pour the filling slowly into the baked tart shell and place in the oven. Bake 30 minutes, or until the filling is set. After the first 20 minutes, or earlier if needed, cover the rim of the shell with foil to prevent overbrowning.

Remove the tart from the oven and let cool slightly on a rack. If you have used a tart pan with a removable bottom, release the tart base from the fluted tart ring.

Let cool a bit longer on the rack, then, with the help of a wide spatula, slide the tart onto a serving plate. Make sure it is completely cool before slicing and serving.

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