Lemon Bars

I didn't have a camera at the ready to record Bill's exultant lemon bar dance, so this happy photo from last summer will have to suffice. Make these lemon bars. Do it now. They cause spontaneous dancing.

The warm filling has to be added to a warm crust for the chemistry to work out correctly, so start making the filling as soon as the crust goes into the oven. Be sure to cool the bars completely before cutting them.

Photo by Tim Connor
Recipe from Baking Illustrated (America's Test Kitchen, 2004)


FOR THE CRUST
1 1/4 cups unbleached all-purpose flour
1/2 cup confectioners' sugar, plus more to decorate the finished bars
1/2 teaspoon salt
1 stick unsalted butter, softened but still cool, cut into 1-inch pieces

FOR THE LEMON FILLING
7 large egg yolks, plus 2 large eggs
1 cup plus 2 tablespoon granulated sugar
2/3 cup from 4 or 5 medium lemons, plus 1/4 cup finely grated zest
1/2 stick unsalted butter, cut into 4 pieces
3 tablespoons heavy cream

1.To line a 9-inch square baking pan, fold two 16-inch pieces of foil or parchment paper lengthwise to measure 9 inches wide. Fit 1 sheet in the bottom of the greased pan, pushing it into the corners and up the sides of the pan (overhang will help in removal of baked bars). Fit the second sheet in the pan in the same manner, perpendicular to the first sheet. Spray the sheets with nonstick cooking spray.

2. Place the flour, confectioners' sugar, and salt in a food processor and process briefly. Add the butter and process to blend, 8 to 10 seconds, then process until the mixture is pale yellow and resembles coarse meal, about three 1-second pulses. Sprinkle the mixture into the prepared pan and press firmly with your fingers into an even layer over the entire pan bottom. Refrigerate for 30 minutes.

3. Adjust an oven rack to the middle position and heat the oven to 350°F. Bake the crust until golden brown, about 20 minutes.

MAKE THE FILLING
1. In a medium non-reactive bowl, whisk together the yolks and whole eggs until combined, about 5 seconds. Add the granulated sugar and whisk until just combined, about 5 seconds. Add the lemon juice, zest, and salt; whisk until combined, about 5 seconds. Transfer the mixture to a medium non-reactive saucepan, add the butter pieces, and cook over medium-low heat, stirring constantly with a wooden spoon, until the curd thickens to a thin sauce-like consistency and registers 170°F (76°C) on an instant-read thermometer, about 5 minutes. Immediately pour the curd through a single-mesh stainless steel strainer set over a clean non-reactive bowl. Stir in the heavy cream; pour the curd into the warm crust immediately.
2. Bake until the filling is shiny and opaque and the center 3 inches jiggle slightly when shaken, 10 to 25 minutes, depending on too many factors to name. Cool on a wire rack to room temperature, about 45 minutes. Remove the bars from the pan using the foil or parchment handles and transfer to a cutting board. Cut into 2 1/2 inch squares, wiping the knife clean between cuts as necessary. Sieve confectioners' sugar over the bars, before serving. Makes 16 bars