Blackberry Napoleon With Lemon Cream

Preparation

1. Step 1

   Make the lemon curd: In a large bowl, whisk together eggs, sugar, salt and lemon zest.

2. Step 2

   Put lemon juice in a medium heavy-bottomed saucepan and bring to a boil over high heat, keeping a close eye on it so it doesn’t boil away. Slowly whisk hot lemon juice into egg mixture, then pour it all back into the saucepan.

3. Step 3

   Cook over medium-high heat, whisking constantly until mixture begins to thicken, about 2 minutes. Continue cooking until the mixture is quite thick, another 2 minutes, then remove from heat. Whisk in the butter until the mixture looks shiny. Set bowl over ice, whisking occasionally until mixture is smooth and cool, then refrigerate. This should yield about 1 ¼ cups. Lemon curd may be prepared a day or two in advance.

4. Step 4

   Heat oven to 375 degrees.

5. Step 5

   Open the puff pastry sheet and lay it flat. Cut the sheet into two strips lengthwise (each about 4 ½ by 12 inches). Set strips side-by-side on a parchment lined baking sheet. Bake on the top rack of the oven until puffed and golden, 20 to 25 minutes, taking care not to overcook. If necessary, tent with foil to keep from getting too brown

6. Step 6

   Let cool on a rack. Once cool, use a serrated knife to cut through the equator of the puff pastry, dividing both strips into 2 thinner pieces. If the interior of the pastry looks pale or undercooked, return to oven for a few minutes, cut-side-up.

7. Step 7

   Whip the heavy cream in a chilled bowl with the vanilla and 2 teaspoons powdered sugar until it holds soft peaks. Fold in the chilled lemon curd with a spatula — it’s OK if the mixture is a little streaky.

8. Step 8

   Assemble: No more than 1 hour before serving, place one of the bottom pieces of baked pastry on a cutting board or a platter. Spread half the lemon-cream mixture across the length.

9. Step 9

   Quickly toss the berries in a bowl with 1 tablespoon powdered sugar. Scatter half the berries in a layer over the lemon cream.

10. Step 10

    Carefully place a top piece of pastry strip on top and press it into place. Keep cool but not refrigerated. Dust top with powdered sugar.

11. Step 11

    Repeat with the other pair of pastry strips, remaining lemon cream and berries.Cut crosswise into wide slices using the serrated knife and serve immediately.