Grolet appareil (18–20cm)
- 500 g whole milk
- 100 g whole eggs
- 90 g sugar
- 50 g cornstarch (poudre à crème)
- 50 g butter
- 2 vanilla pods
Thierry Marx — richer version (18cm)
- 130 g water
- 325 g whole milk
- 200 g crème fleurette
- 3 eggs
- 3 egg yolks
- 160 g sugar
- 60 g cornstarch
- 1 vanilla pod
Pâte brisée (Thierry Marx)
- 200 g flour
- 20 g icing sugar
- 2 g salt
- 100 g butter
- 2 egg yolks
- 30 ml water
The flan pâtissier is one of the most unforgiving pastries to unmould: the custard must be cold all the way through or it collapses on the plate. Make it the day before and refrigerate overnight. The characteristic dark top requires high initial heat and a confident hand — do not open the oven during the first 10 minutes.
Method
Crust
- Make the pâte brisée: rub butter into flour, icing sugar, and salt until sandy. Add yolks and water, bring together. Rest 1h in the fridge.
- Roll to 3mm. Line a 18–20cm ring or hinged mould — press firmly into the sides and leave overhang. Freeze 30 min minimum.
- No blind baking needed — the flan crust bakes directly with the custard.
Alternatively, use pâte feuilletée scraps for a flakier, more textured base.
Custard (appareil à flan)
- Infuse milk with split vanilla pods — bring to a boil, cover, rest 10 min off heat.
- Whisk eggs (or yolks) with sugar until pale. Whisk in cornstarch until smooth.
- For the Thierry Marx version: whisk all liquids (water + milk + cream) directly into the egg-sugar-starch mixture without tempering — combine cold.
- For the Grolet version: temper — pour hot milk over the egg mixture in a thin stream, whisking. Return to the pan and cook over medium heat, whisking constantly, until it thickens and bubbles. Cook for 1 full minute after the first bubble. Off heat, whisk in butter.
Bake
- Pour the custard directly into the unbaked crust — it should fill to within 5mm of the top. Smooth the surface.
- Bake: 10 min at 220°C, then 30–35 min at 180°C. The top should be deeply browned (almost burnt-looking) with a slight jiggle remaining in the centre.
- Cool to room temperature, then refrigerate at least 3–4 hours. Overnight is essential for clean unmoulding.
- Unmould cold. Trim the pastry edges with a sharp knife if needed.
The custard is still liquid when it leaves the oven — it sets as it cools. Do not refrigerate until it has cooled to room temperature, or condensation will form.
Background
The dark top is structural, not decorative. The high initial heat (220°C) creates a skin on the custard surface that holds the shape during the rest of the bake. Without it, the custard surface remains fragile and tears on unmoulding. The Marx recipe uses water alongside the milk and cream — the extra liquid thins the mixture and allows the top to brown more evenly before the custard sets through.
Grolet's recipe uses cornstarch alone (no flour) — this gives a cleaner, smoother set with no floury aftertaste. The butter added off heat enriches and softens the texture. The Marx version with whole eggs and cream is richer and more unctuous; the Grolet version is cleaner and more vanilla-forward.
Cooling notes from December 2022: allow 3–4 hours at room temperature before moving to the fridge, then overnight. Cutting too early gives a custard that oozes. The pastry at 6mm thickness (rather than 4mm) is more forgiving and holds better under a generous filling.
Mistakes I've Made
- Unmoulding warm. The custard collapses and spills out. Always unmould fully cold.
- Crust too thin. Tears during unmoulding and the sides lose their shape. 6mm is more forgiving than 4mm for this application.
- Not cooking the custard long enough. It sets weakly and slumps when cut. The 1-minute post-bubble boil is essential for proper starch activation.
- Opening the oven in the first 10 min. The custard surface collapses. Let the skin set fully before opening.
Sources
- Flan Pâtissier | Grolet —
- Flan Pâtissier | Thierry Marx —
- Flan Pâtissier | 750g —
- Flan Pâtissier San Francisco —