Coffee Soufflé — a hot espresso pastry-cream soufflé

i. Origin & history

The soufflé is one of the emblems of French cooking. Its name means "puffed up" or "blown", from souffler, and dishes of whipped egg baked until risen appear in French cookbooks from the eighteenth century. In the nineteenth century the great chefs of Paris, Antonin Carême among them, turned the soufflé into a set piece of haute cuisine, made possible in part by more controllable ovens. It became a test of a kitchen's skill and timing, served the instant it came out of the oven.

Sweet soufflés developed two main structures. One is based on a fruit purée or syrup, as in the berry soufflé. The other — the older and more classic style — is built on a thick custard base: a crème pâtissière, or a cooked paste of butter, flour and milk known as a panade or bouillie, enriched with egg yolks. This base carries flavours such as vanilla, chocolate, liqueur and coffee, and the coffee soufflé belongs firmly to this family.

Coffee became a classic flavour of French pâtisserie in the nineteenth century, as café culture took hold in Paris; coffee éclairs, coffee religieuses and moka buttercream cakes all date from the same period. The soufflé au café was a natural extension, and it became a regular on bistro and brasserie menus alongside the vanilla and Grand Marnier soufflés, often served with a jug of crème anglaise.

It should not be confused with the soufflé glacé au café, a frozen dessert of coffee parfait set in a ramekin with a paper collar so that it appears to have risen above the rim. That is a mousse frozen to look like a soufflé; the dish on this page is the real, hot one.

ii. Getting coffee flavour into a soufflé without drowning it

The challenge with a coffee soufflé is that flavour and structure pull in opposite directions. The base must be thick enough to support a large volume of egg whites, so you cannot simply pour in a cup of espresso: the extra water thins the base, deflates the whites and produces a soufflé that rises then weeps. At the same time, the whites dilute every flavour in the base, so the coffee has to be strong enough to survive being more than doubled in volume.

The solution is concentration. Instant espresso powder dissolved directly in the hot milk gives intense coffee flavour with no added water. Alternatively, infuse the milk with coarsely ground coffee beans for 20 minutes and strain it, which gives a rounder, more aromatic flavour. A tablespoon of coffee liqueur stirred into the base adds depth and a little sweetness without loosening it much.

The base itself is a pastry cream thickened with a mix of flour and cornflour, cooked until it boils and is very thick. Boiling is essential: the starch must fully gelatinise, both to thicken the base and to neutralise enzymes in egg yolk that would otherwise thin it. A thick base gives the whites something to cling to, producing a fine, even, custardy crumb.

From there, the rules are those of every soufflé: firm, glossy egg whites stabilised with sugar; gentle folding; buttered and sugared ramekins brushed upwards; a hot oven and a preheated tray. A custard-based soufflé is slightly more forgiving than a fruit one, because the yolks and starch give the structure more body, but it still waits for nobody.

iii. Ingredients

Makes 6 servings · scroll the side panel to adjust

• 250 ml whole milk
• 2 tbsp instant espresso powder
• 3 egg yolks
• 50 g caster sugar, for the base
• 20 g plain flour
• 10 g cornflour
• 15 g unsalted butter
• 1 tbsp coffee liqueur (optional)
• 5 egg whites, at room temperature
• 50 g caster sugar, for the whites
• 1 pinch salt
• 20 g soft butter, for the ramekins
• 2 tbsp caster sugar, for the ramekins
• 1 tbsp icing sugar or cocoa, to dust

Instant espresso powder is the most reliable way to get strong coffee flavour without extra liquid; a good-quality instant coffee works, though the flavour is softer. To use real coffee instead, warm the milk with 25 g of coarsely ground beans, leave to infuse for 20 minutes, then strain and top up to 250 ml. Coffee liqueur such as Kahlúa or Tia Maria is optional; dark rum or brandy also suit coffee. The extra egg white (five whites to three yolks) gives a lighter, taller soufflé. Leftover yolks can go into a zabaione or crème anglaise to serve alongside.

iv. Method

1. Brush six 200 ml ramekins with soft butter using upward strokes, coat the insides with sugar and tip out the excess. Chill until needed.
2. Heat the milk with the espresso powder until steaming and the coffee has dissolved. Whisk the yolks, 50 g sugar, flour and cornflour until smooth, then pour on the hot milk, whisking.
3. Return to the pan and cook over a medium heat, whisking constantly, until the mixture thickens, comes to the boil and bubbles for 1 minute. It should be very thick and glossy. Remove from the heat and whisk in the butter and liqueur.
4. Transfer to a large bowl, press clingfilm onto the surface and cool until just warm. Heat the oven to 190 °C (375 °F), fan 170 °C, with a baking tray on the middle shelf.
5. Whisk the egg whites with the salt to soft peaks, then add 50 g sugar a spoonful at a time and whisk to firm, glossy peaks.
6. Beat the coffee base smooth, stir in a quarter of the whites to loosen it, then gently fold in the rest in two additions until no white streaks remain.
7. Fill the ramekins to the top, level with a palette knife and run your thumb around the rim to form a small groove.
8. Bake on the hot tray for 12–14 minutes, until risen 3–4 cm above the rim, golden on top and still slightly wobbly in the centre. Do not open the oven for the first 10 minutes.
9. Dust with icing sugar or cocoa and serve immediately.

v. Tips & common mistakes

• Do not add brewed coffee to the base. Extra liquid thins the base and leaves the soufflé watery. Use espresso powder or infuse the milk instead.
• Boil the pastry cream properly. If the base does not bubble for a full minute, it stays thin and can turn runny as it stands.
• Loosen the base before folding. A stiff, cool base is hard to fold into whites. Beat it smooth and stir in a quarter of the whites first.
• Make the base ahead, whip the whites at the last minute. The base keeps for a day; the whites must be whipped and folded just before baking.
• Check doneness by the wobble. A gentle shake should show a soft quiver in the centre. Overbaked soufflés are dry and cakey; underbaked ones collapse into soup.
• Serve at once. A soufflé starts to fall within two minutes. Have spoons, plates and sauce ready before you open the oven.

vi. Variations

For a mocha soufflé, melt 40 g dark chocolate into the hot base. A coffee and cardamom soufflé infuses the milk with a few crushed cardamom pods, in the style of Middle Eastern coffee. A vanilla soufflé leaves out the coffee and uses a split vanilla pod, and a Grand Marnier soufflé flavours the base with orange liqueur and zest. The cold relative, soufflé glacé au café, is a frozen coffee parfait set high in a collared dish.

Other coffee desserts on DessertCat include the Italian espresso panna cotta and the iced coffee cake. For the fruit-based soufflé method, see the berry soufflé, and for a cold, airy dessert with no oven timing, the hazelnut mousse or white chocolate mousse.

vii. Serving & storage

Serve the soufflé the instant it leaves the oven, on a small plate with a napkin under the ramekin. At the table, break open the top and pour in a little cold crème anglaise, vanilla cream or chocolate sauce, or drop in a small scoop of vanilla ice cream. A small biscuit, such as a tuile or almond biscotti, adds crunch, and a glass of dessert wine or a digestif suits it after dinner.

Baked soufflés cannot be kept. You can, however, make the coffee base up to a day ahead and keep it in the fridge with clingfilm on the surface; warm it slightly and beat smooth before folding in freshly whipped whites. The ramekins can be prepared a day ahead. Filled, unbaked soufflés will hold in the fridge for up to 30 minutes before baking.

ix. More from French

• Berry Soufflé — fruit-purée soufflé
• Hazelnut Mousse — praline mousse
• White Chocolate Mousse — silky and pale
• Espresso Panna Cotta — set coffee cream
• Iced Coffee Cake — coffee layer cake
• Zabaione — Italian whipped yolk custard