Asparagus Custard Tart

Ingredients for Asparagus Custard Tart

• 130g plain flour

• 1/2 teaspoons salt

• 3/4 stick (6 tablespoons ) cold unsalted butter, cut into 1/2-inch cubes

• 1 large egg, lightly beaten

• 1 medium leek (white and pale green parts only), quartered lengthwise, then cut crosswise into 1/3-inch pieces

• 450g medium asparagus, trimmed

• 1 tablespoon unsalted butter

• 1/2 teaspoons salt

• 1/2 teaspoons black pepper

• 325ml double cream

• 3 large eggs

• 2 teaspoons finely chopped fresh tarragon

• 2 teaspoons water

• parchment paper

• a 9 1/4-inch flan ring* (see cooks' note, below)

How to make Asparagus Custard Tart

Blend together flour, salt, and butter in a bowl with your fingertips or a pastry blender (or pulse in a food processor) until most of mixture resembles coarse meal with some small (roughly pea-size) butter lumps. Drizzle evenly with egg and gently stir with a fork (or pulse in processor) just until a dough forms.

Turn out dough onto a lightly floured surface and divide into 4 portions. With heel of your hand, smear each portion once or twice in a forward motion to help distribute fat. Gather dough into a ball, then flatten into a 5-inch disk. Chill dough, wrapped in plastic wrap, until firm, at least 30 minutes.

Wash leek in a bowl of cold water, agitating water, then lift out leek and pat dry.

Cook asparagus in a wide 4- to 5-quart pot of boiling salted water , uncovered, until just tender, about 5 minutes. Transfer asparagus with tongs to a bowl of ice and cold water to stop cooking, then drain and pat dry. Cut off and reserve tips (leave more stalk if asparagus is thin), then thinly slice stalks crosswise.

Heat butter in a 10- to 12-inch heavy skillet over moderately low heat until foam subsides, then cook leek with 1/4 teaspoons salt, stirring, until softened, 6 to 8 minutes. Stir in sliced asparagus and 1/4 teaspoons pepper and remove from heat.

Put oven rack in middle position and preheat oven to 191°C.

Line a baking sheet with parchment paper and put flan ring in centre of baking sheet. Roll out dough on a lightly floured surface with a floured rolling pin into an 11-inch round, then fit dough inside flan ring, pressing dough against bottom edge and side of ring. Run rolling pin over top edge of ring to cut off excess dough.

Whisk together cream, 2 eggs, tarragon, and remaining 1/4 teaspoons salt and 1/4 teaspoons pepper. Lightly beat remaining egg with water in a small bowl and brush tart shell all over with some egg wash. Spoon asparagus mixture into shell, spreading evenly, then pour cream mixture over asparagus.

Bake tart until filling is just beginning to set but still loose on top, 20 to 25 minutes. Scatter asparagus tips over top, pressing lightly if necessary to help them settle into filling, then continue to bake until custard is golden and just set but still slightly wobbly in centre, about 30 minutes more (custard will continue to set as it cools).

Cool tart on baking sheet on a rack until warm, about 30 minutes. Loosen edge with a small sharp knife, then lift off flan ring. Serve warm or at room temperature, cut into wedges.

*Available at cookware stores and Bridge Kitchenware (212-688-4220; bridgekitchenware.com).

Disclaimer

While every effort has been made to ensure the information is accurate and up to date, individual needs may vary and dietary requirements can differ based on personal health conditions. Always check food labels and allergen information before preparing or consuming any recipe. If you have specific health concerns, allergies, intolerances, or are following a medically prescribed diet, seek advice from your GP, pharmacist, or a registered dietitian before making significant changes to your diet or lifestyle.