Makes 8 servings
Almost as soon as you say “rhubarb,” you’re tempted to say “strawberries.” They grow together, ripen at about the same time and play a lively point-counterpoint of sweet and not-sweet. And yet, when it comes to this tart, I don’t want too many strawberries. I want them there for color and sweetness, but not so many that they cut away too much of rhubarb’s edge or give in too easily to the oven’s heat and go soft and watery.
The rhubarb for the tart filling is macerated in sugar — a nice move, because the sugar and juices become a rhubarb-flavored syrup that you can use in the custard, a classic cream-and-egg custard flavored with vanilla and (if you’d like) a little rose extract. It’s everything you want in a spring-into-summer dessert: It’s beautiful, aromatic and delicious.
Working Ahead
The rhubarb must be macerated in the sugar for at least 30 minutes, and it can sit for up to 2 hours.
Cut the rhubarb into slices about ½ inch thick. (If you’ve got fat stalks, halve them the long way first and then slice.) You should end up with about 3 cups rhubarb. Put the pieces in a bowl, stir in the ½ cup sugar and let sit, stirring now and then, for about 30 minutes. You want a syrup to form. (You can macerate the rhubarb for up to 2 hours.)
When you’re ready to bake, center a rack in the oven and preheat it to 375 degrees F. Line a baking sheet with parchment paper or a silicone baking mat.
Drain the rhubarb, reserving the syrup.
Whisk the heavy cream, the remaining ⅓ cup sugar, the egg and yolk together in a bowl until blended. Stir in the vanilla, the rose extract, if you’re using it, and the rhubarb syrup.
Place the tart shell on the baking sheet and spoon in the rhubarb, nudging it so that it covers the bottom. Pour the custard over the rhubarb (it should be just enough to fill the shell with a little room to spare; if you think you’ve got too much and that it might bake over the sides of the shell, hold back whatever’s necessary). Add the strawberries, arranging them so that they speckle the top evenly.
Bake the tart for 50 to 60 minutes (cover the edges of the crust if it starts to brown too deeply), until the custard has risen slightly but evenly and a tester inserted close to the center of the tart comes out clean. Transfer the baking sheet to a rack and let the tart cool to just slightly warm or room temperature.
Serve the tart plain, with whipped cream or with whipped cream and berries.
Storing: This tart is really best enjoyed soon after it’s baked, but you can keep it for several hours at room temperature. Refrigerate any leftovers — they won’t be as luxurious as just-baked, but they’ll still be satisfying.