Lemon Bar Tart

We do not have a 9 inch pan, we do not have it, Sam I am.

We do not like them in a square, it's so passé I wouldn't dare.

A round pan works, 'cuz in a pinch, you just pull out your bag of tricks.

Like cutting bars in the form of a kite, or sifting powdered sugar oh so white.

This tart, alas, dirties many a bowl, but the creamy custard's got me sold.

The crust's a very good bake, it's crisp for heaven's sake!

Lemon Bar Tart
Yield: One tart and one nibbling pan (4x4). Alternatively, a 9 inch square pan of traditional lemon bars.

Ingredients:

For the crust:

• 1 1/4 cups (6 1/4 ounces) all-purpose flour
• 1/2 cup (2 ounces) powdered sugar, plus more for decoration
• 1/2 teaspoon kosher salt
• 8 tablespoons softened unsalted butter, cut into 16 pieces

For the filling:

• 7 large egg yolks
• 2 large eggs
• 1 cup + 2 tablespoons (7 7/8 ounces) granulated sugar
• 2/3 cup lemon juice (2 1/2 lemons gave me more than enough, but you might need more if they're small or dry)
• 1/4 cup lemon zest (I needed 4 lemons for this)
• pinch salt
• 4 tablespoons unsalted butter, cut into 4 pieces
• 3 tablespoons heavy cream, cold

Method:

1. Prepare the pans. If you're using a tart pan, butter the inside of the dish and disk, and butter a small, ~4x4 inch ramekin of some sort (this is for snacking, because the recipe is not designed for a tart pan!). If you're using a 9x9 inch pan, butter it and make a parchment or aluminum foil sling so it's easier to take them out of the pan.
2. For the crust: In a food processor, pulse the flour, powdered sugar, and salt a couple of times to combine. Add the butter chunks and pulse a few more times until the mixture looks like crumbs. Press into prepared pans, going up the sides if you're using a tart pan. Chill in the refrigerator for 30 mins.
3. Preheat oven to 350 degrees and position the rack in the middle of the oven. Bake crust for about 20 minutes, or until golden brown.
4. While the crust is baking, prepare the filling: whisk eggs and sugar together in a medium saucepan. Add lemon juice, lemon zest, and salt and whisk again to combine. Add butter and cook over medium-low heat until the mixture reaches 170 degrees F, or until it thickens significantly (you'll feel it).
5. Strain custard into a medium sized bowl, then stir in the cold cream. Pour directly into the hot crusts and bake again for 10-12 minutes, or until the filling still jiggles a bit.
6. Cool on wire racks to room temperature, about 45 minutes, before taking out of the pan and cutting. 
7. *While it looks beautiful to sift powdered sugar over the whole tart, it won't last in the fridge overnight so just sift over the pieces you're going to serve (ignore the pictures above which I did for beauty's sake sifting over the whole thing). Keeps in the refrigerator a few days, but top will get wet. Just blot off the moisture, sift some sugar over the whole shebang, and serve!

Recipe from Baking Illustrated, modified for pan size.