Classic Lobster Thermidor with Gruyère Crust

⏱ 60 min · Serves 2

The grandest way to eat lobster: sweet poached tail meat folded through a brandy, mustard and tarragon cream, piled back into the shells and glazed under the grill until blistered and golden. Old-school French luxury, and worth every minute.

Per serving: 790 kcal · 52.0g protein · 10.0g carbs · 58.0g fat

Ingredients

• 2 live or cooked lobsters, about 600g each
• 30g unsalted butter
• 2 banana shallots, very finely chopped
• 150g chestnut mushrooms, finely diced
• 3 tbsp brandy or Cognac
• 120ml dry white wine
• 200ml double cream
• 1 tsp Dijon mustard
• 1/2 tsp English mustard
• 1 tbsp chopped fresh tarragon
• 1 tsp chopped fresh chives
• 1 tbsp lemon juice
• 50g Gruyère, finely grated
• 20g Parmesan, finely grated
• Pinch of cayenne pepper
• Sea salt and white pepper
• Lemon wedges and green salad, to serve

Method

1. If using live lobsters, chill them in the freezer for 30 minutes, then plunge into a large pan of heavily salted boiling water for 7 minutes. Lift out and cool.
2. Twist off the claws and crack them; pick out all the meat. Split each lobster lengthways through the head with a heavy knife, remove the tail meat and discard the dark intestinal tract and the gritty head sac. Reserve the empty half-shells and wipe them clean.
3. Cut all the lobster meat into bite-sized chunks. Cover and keep cool.
4. Melt the butter in a wide frying pan over a medium heat. Soften the shallots for 3 minutes without colouring, add the mushrooms and cook 5 minutes until any liquid has evaporated.
5. Pour in the brandy and let it bubble away for 30 seconds (flame it if you're confident). Add the wine and reduce until only a couple of tablespoons of syrupy liquid remain.
6. Stir in the cream and both mustards. Simmer gently for 4-5 minutes until thick enough to coat a spoon. Season with salt, white pepper and cayenne, then stir in the tarragon, chives and lemon juice. Cool slightly.
7. Fold the lobster meat through the sauce, keeping a few good chunks for the top. Heat the grill to high.
8. Sit the shells on a baking tray (steady them with scrunched foil). Spoon in the mixture, mounding it slightly, then scatter with the mixed Gruyère and Parmesan.
9. Grill 12-15cm from the heat for 3-4 minutes until bubbling and deeply golden. Serve at once with lemon wedges and a sharply dressed salad.