Roasted Rhubarb and Lemon Cream

Lemon curd whizzed in a food processor for a minute or so becomes a lighter-than-air, creamy sauce for these sweet and tangy dessert crepes, which were created by pastry chef and cookbook author Kir Jensen of The Sugar Cube food cart in Portland, Oregon. If you're using fresh rhubarb, pick out the darkest red stalks you can find—they have the best flavor and color.

Ingredients

For the Vanilla-Roasted Rhubarb:
 

• 1/2 vanilla bean, split

• 2 tablespoons unsalted butter, melted

• 1-1/2 to 1-3/4 cups/300 to 350 g granulated sugar

• 1-1/2 tablespoons fresh lemon juice (from 1/2 medium lemon)

• 1/4 teaspoon kosher salt

• 2 pounds/910 g fresh or thawed frozen rhubarb, cut into 1/2-inch/12-mm pieces

For the Lemon Cream:

• 1 cup/225 g unsalted butter, cut into 1-inch/2.25-cm pieces, at room temperature

• 4 large eggs plus 4 large egg yolks

• 1 cup/200 g granulated sugar

• Grated zest of 2 medium lemons (2 tablespoons)

• 1/2 cup fresh lemon juice, strained (from 5 to 6 medium lemons

• Pinch of kosher salt

• 12 Almond-Brown Butter Crepes or your choice

• Confectioners' sugar, for sprinkling

Instructions

Make the Vanilla-Roasted Rhubarb:

1. Position rack in the center of the oven and preheat to 400°F/200°C/gas. Butter a 9-x-13-inch/23-x33-cm shallow roasting pan or baking dish.

2. Scrape the seeds from the vanilla bean with the back of a knife and put them in a large bowl, along with the pod. Add the butter, granulated sugar, lemon juice, and salt and toss with the rhubarb to coat. Leave at room temperature until juicy, about 15 minutes. Pour the rhubarb and juices into the prepared pan and roast until the rhubarb is tender and the juices are bubbling, 15 to 20 minutes (fresh rhubarb will cook more quickly). Try not to overcook the rhubarb, or it will turn into mush.

3. Using a slotted spoon, transfer the rhubarb to a clean large bowl and let it cool. Pour the juices from the roasting pan into a small saucepan over medium-high heat and bring to a boil. Let the juices boil until reduced to a thick syrup, 2 to 8 minutes. Remove the pan from the heat and let the syrup cool for at least 5 minutes. Gently fold it back into the roasted rhubarb. Set the rhubarb aside to cool slightly before assembling the crepes. (You can make the rhubarb to this point up to 1 week ahead. Store it in an airtight container in the refrigerator. Let it come to room temperature or warm it gently before proceeding with the recipe.)

Make the Lemon Cream:

1. Fill a large bowl with ice water and set it aside.

2. Whisk together butter, eggs, egg yolks, granulated sugar, lemon zest, lemon juice, and salt in a medium heavy-bottomed saucepan and place over medium heat. Cook, stirring frequently with a wooden spoon, until the butter has melted and the sugar has dissolved, 3 to 5 minutes. Continue cooking, scraping the bottom and sides of the pan almost constantly (if the eggs get too hot, they'll scramble), until the mixture has thickened and reached 170°F/77°C on an instant-read thermometer, 5 to 6 minutes more. (It should coat the back of the spoon.) Immediately remove the pan from the heat and strain the mixture through a fine-mesh sieve into a nonreactive bowl. Press plastic wrap onto the surface of the lemon mixture so it doesn't form a skin. Put the bowl into the ice bath and let it chill for 20 minutes.

3. Transfer the lemon mixture to a blender or food processor and whiz it for about 1 minute. It will lighten in color and become airy and velvety smooth. Transfer the lemon cream to a clean bowl and press plastic wrap directly onto its surface. Chill in the refrigerator until cold. (The lemon cream can be made up to 1 week ahead and stored in an airtight container in the refrigerator. Let it sit out at room temperature for at least 20 minutes, and stir it to loosen, before serving.)

4. Position a rack in the center of the oven and preheat to 300°F/150°C/gas. Put the crepes on a large plate and cover the plate with foil. Heat the crepes in the oven until they're hot, about 10 minutes.

To assemble:

Lay the crepes presentation-side down on a clean work surface. Spoon 3 tablespoons of the rhubarb into the center of each one. To fold the crepes, lift an edge of each crepe and fold it over the rhubarb, pleating about six times as you work your way around the crepe to create a pleated border. The pretty red rhubarb filling will show in the center. Transfer the crepes to dessert plates and sprinkle each with confectioners' sugar. Serve with a dollop of the lemon cream on top.