1 cup maple syrup, preferably grade B
3 1/2 cups heavy cream
7 large egg yolks
1/8 teaspoon salt
1/2 cup plus 2 tablespoons sugar
1/2 teaspoon light corn syrup
Whipped crème fraîche for serving, optional
1/4 cup walnuts
1/2 cup (1 stick) unsalted butter, softened
1/3 cup confectioners' sugar
1 large egg, lightly beaten
1 1/2 cups all-purpose flour
1/2 cup plus 2 tablespoons almond flour
1/2 teaspoon salt
1. To prepare the flan, place the maple syrup in a large, heavy saucepan. Set it
over low heat and let simmer until the syrup is reduced by a quarter (to 3/4
cup), 15 to 20 minutes.
2. Add the cream to the syrup and
stir until mixture is smooth and comes back to a simmer.
3. In a large bowl, whisk the egg
yolks until smooth. Add a little of the hot maple cream into the eggs to warm
them, whisking constantly to keep the yolks from curdling. Pour the mixture into
the saucepan, whisking the cream constantly. Strain the mixture into a bowl,
stir in the salt, and chill for at least 2 hours and up to 5 days.
4. Preheat oven to 300°F. Place 1/4
cup water in a small saucepan over medium heat, then add the sugar and corn
syrup. Raise the heat to high and cook, swirling the pan occasionally, until the
mixture becomes a dark amber caramel, 7 to 10 minutes. Immediately pour the
caramel into an 8-inch round nonstick cake pan, tilting to make sure the sides
are well coated. Work quickly so the caramel doesn't harden. If it does, re-warm
it over low heat.
5. Pour the maple custard into the
caramel-coated cake pan. Place it in a baking pan and carefully move it to the
oven rack. Pour enough very hot water into the baking pan to reach two thirds of
the way up the side of the cake pan. Cover the baking pan with foil and prick
all over with a fork. Bake the flan for about 1 hour, then lift off a corner of
the foil to vent the steam. Re-cover the pan and continue to bake until the flan
is set around the edges but still slightly jiggly in the center, about 45
minutes longer. Remove the flan from the baking pan and transfer to a rack. Let
cool at room temperature, then cover and refrigerate overnight.
6. To prepare the walnut crust,
preheat oven to 350°F. Spread the nuts out on a baking sheet and toast them in
the oven, stirring once or twice, until they smell nutty, about 10 minutes.
Transfer the pan to a wire rack to cool.
7. Using a food processor, pulse the
walnuts until they are finely ground, then reserve. In the bowl of an electric
mixer fitted with the paddle attachment, beat the butter and confectioners'
sugar until combined, about 1 minute. Beat in the egg. In a medium bowl, whisk
together the flour, almond flour, walnuts, and salt. Add the flour mixture to
the butter mixture in 2 batches, scraping down the sides of the bowl between
additions. Mix until the dough just holds together. Scrape the dough onto a
piece of plastic wrap and form it into a disk. Wrap it and chill for at least 1
hour, until firm.
8. Preheat oven to 325°F. On a
lightly floured surface, roll out the dough 1/8 inch thick into a 12-inch round.
Fit the dough into a 9-inch quiche pan. Trim away any excess dough, then use a
fork to prick the crust all over. Bake the tart crust until it's pale golden,
about 25 minutes. Transfer the pan to a wire rack to cool. (The tart shell can
be made 8 hours ahead and kept at room temperature or frozen.)
9. To unmold the flan, run a small
knife around the sides of the cake pan, then invert the flan into the baked tart
shell. Serve with whipped crème fraîche, if desired.
For individual flans without crust, divide the caramel and then the maple
custard evenly among eight 4-ounce glass or ceramic ramekins. Bake as directed
for 1 hour and 30 minutes, venting the steam after 45 minutes.
Makes 8 servings.