Lobster Thermidor

How to Make Lobster Thermidor

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1. Split each lobster in half lengthways with a large, sharp knife, cutting from the head to the tail. Remove the meat from the tail and claws. Discard the stomach sac in the head and the dark vein running along the tail. Cut the meat into bite-size chunks and keep the empty shell halves.

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2. Melt the butter in a saucepan over medium heat. Add the shallots and cook for 3 minutes, until soft but not coloured.

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3. Add the wine and brandy and boil for 3 minutes, until reduced by about half. Pour in the cream and the mustard and simmer for 4 minutes, stirring, until thick enough to coat the back of a spoon.

   Mark done Start 3 min timer

4. Stir in the tarragon, lemon juice and cayenne and season with salt. Fold in the lobster meat and warm through for 1 minute.

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5. Heat the grill to high. Set the shell halves on a baking tray and spoon the mixture back into them. Sprinkle with the cheese.

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6. Grill for 3 to 4 minutes, until the top is golden and bubbling. Serve at once with lemon wedges and salad.

   Mark done Start 3 min timer

Tips for Making Lobster Thermidor

• Do not overcook the lobster. It is already cooked, so it needs only to be warmed in the sauce, then browned briefly. Long heating makes it rubbery.
• Reduce the sauce until it is thick. A thin sauce runs out of the shell and makes the gratin soggy.
• Use fresh tarragon if you can. Its aniseed flavour is the signature of the dish, and dried tarragon is a poor substitute.

Common Substitutions & Variations

• Double cream won't whip if you swap it, but for the cooking itself, full-fat crème fraîche or a lower-fat single cream works in its place.
• A dry vermouth keeps for longer than an open bottle of white wine and is the closer swap than a random white left in the fridge; for an alcohol-free version, use the same amount of stock with a squeeze of lemon.

What to Serve with Lobster Thermidor

• Green salad
• Chips
• Chilled white Burgundy

Storing & Reheating Lobster Thermidor

Best eaten straight away. The filled shells can be prepared up to 6 hours ahead, covered and chilled, then grilled just before serving.

Lobster Thermidor FAQ: Common Questions

Lobster Thermidor Nutrition

Per serving, calculated from the ingredient list. Treat these as an estimate — brands and cuts vary.