Flan patissier is a thick vanilla custard tart with a golden, flaky puff pastry base and a creamy filling that slices cleanly.
The custard is cooked on the stove first, then baked in the pastry until set, and the tart needs several hours of chilling to firm up. Count on just over 5 hours from start to slice, with roughly an hour of active work.
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Why This Flan Patissier Recipe Works
The filling is made like a thick pastry cream, with egg yolks, cornstarch, and a vanilla bean, so it sets firm in the oven instead of staying runny.
Cold butter stirred in at the end makes the custard glossy and smooth. A whole egg adds extra structure so the filling slices neatly.
Store bought puff pastry saves hours and gives a crisp, buttery base. Chilling the finished tart is what turns the custard from soft to sliceable.
Ingredients for Flan Patissier
- 4 1/4 cups whole milk
- 2 vanilla beans, seeds scraped, pods reserved
- 1 cup superfine sugar
- 7 large egg yolks, about 4 oz
- 1 large egg
- 7 tbsp cornstarch
- 3 1/2 tbsp cold unsalted butter, cubed
- 2 sheets frozen puff pastry, 10 inch squares, thawed
- 1 egg yolk, whisked, for brushing
- 1 tbsp unsalted butter, for greasing the pan
Vanilla beans. Scrape the seeds into the milk and add the pods too, so the custard tastes of real vanilla. Vanilla bean paste is a fair substitute.
Egg yolks. Yolks give the custard its color and richness. Save the whites for meringues or an omelet.
Cornstarch. Cornstarch thickens the custard so it holds its shape once chilled. Measure it exactly.
Puff pastry. Choose an all butter sheet if you can find one. Keep it cold until you roll it out.
Cold butter. A few cubes stirred in off the heat give the custard a silky finish.
How to Make Flan Patissier
1. Infuse the milk Warm the milk with the vanilla seeds and pods over medium heat until it just simmers.
2. Whisk the yolk base Whisk the sugar, yolks, whole egg, and cornstarch until smooth and pale.
3. Temper the eggs Slowly whisk the hot milk into the yolks, a little at a time, so the eggs do not scramble.
4. Thicken the custard Return it to the pan and stir constantly over medium heat until it is thick and bubbling, then cook 1 minute more.
5. Finish and cool Off the heat, stir in the cold butter until smooth. Press plastic wrap against the surface and cool to room temperature.
6. Line the pan Heat the oven to 350 degrees F. Grease a 9 inch tart pan, stack the two pastry sheets, roll them out, and press into the pan. Trim the edge and brush it with egg yolk.
7. Fill and bake Pour in the cooled custard and bake 40 to 45 minutes until set and golden, with the center at 160 degrees F.
8. Cool and chill Cool to room temperature, then chill at least 3 hours before slicing.
How to Serve Flan Patissier
Cut the chilled tart into 10 slices with a sharp knife and serve with fresh berries or a dusting of powdered sugar. It makes a nice partner on a dessert table next to a classic cheesecake, lemon layer cake, and streusel coffee cake, with a few sugar cookies on the side.
How to Store and Reheat Flan Patissier
Cover and refrigerate leftovers for up to 3 days. Do not leave the tart out for more than 2 hours, since it is an egg and milk custard. Freezing is not recommended because the custard turns watery and the pastry loses its crispness when thawed.
Tips and Variations for Flan Patissier
Stir constantly. Keep a whisk moving along the bottom and corners of the pan so the custard does not scorch.
Strain if needed. Pour the cooked custard through a sieve for an extra smooth filling.
Keep the pastry cold. Cold pastry puffs better, so chill the lined pan for 15 minutes before baking if the kitchen is warm.
Cool the custard first. Hot custard melts the pastry and makes a soggy base, so let it cool to room temperature.
Use a dark pan. A metal tart pan browns the base better than glass.
Vanilla swap. Use 1 tablespoon vanilla bean paste if you cannot find whole beans.
Add fruit. Serve slices with berries or sliced stone fruit for a fresh contrast.
Chill long enough. The tart needs at least 3 hours to set, and this UW Extension leftovers guide has general advice on cooling and storing egg dishes.
Frequently Asked Questions About Flan Patissier
How do you know when flan patissier is set?
The center barely jiggles and the top is golden brown. It reaches 160 degrees F in the middle.
Can I make flan patissier a day ahead?
Yes. It is best made a day ahead since the chilling time is long.
Why did my flan patissier crack?
It was likely baked too long or at too high a temperature. Pull it when the center still has a slight wobble.
Do I need to blind bake the pastry?
No. The pastry bakes along with the custard.
Can I use homemade pastry?
Yes, any rich butter pastry works, but store bought puff pastry makes the tart much quicker.
Flan Patissier with Vanilla Custard and Puff Pastry
Equipment
- Tart pan, 9 inch
- Saucepan
- Whisk
- Rolling Pin
- Fine mesh sieve
Ingredients
Main Ingredients
- 4 ¼ cup whole milk
- 2 vanilla beans seeds scraped, pods reserved
- 1 cup superfine sugar
- 7 large egg yolks about 4 oz
- 1 large egg
- 7 tbsp cornstarch
- 3 ½ tbsp unsalted butter cold, cut into cubes
- 2 sheets frozen puff pastry 10 inch squares, thawed
- 1 egg yolk whisked, for brushing the pastry
- 1 tbsp unsalted butter for greasing the pan
Instructions
Cooking
- Heat the milk. Simmer the milk with the vanilla seeds and pods, then remove from the heat.
- Mix the base. Whisk the sugar, yolks, egg, and cornstarch until smooth.
- Temper. Whisk the hot milk into the yolk mixture gradually, then return everything to the pan.
- Cook. Stir constantly over medium heat until thick and bubbling, about 1 minute more, then whisk in the cold butter.
- Cool. Cover the surface with plastic wrap and let the custard cool to room temperature.
- Prepare the crust. Preheat to 350 degrees F, grease a 9 inch tart pan, press in the rolled pastry, trim, and brush the rim with yolk.
- Bake. Fill with custard and bake 40 to 45 minutes until set and golden, reaching 160 degrees F in the center.
- Chill. Cool to room temperature, then refrigerate at least 3 hours before slicing.
