James Martin Lobster Thermidor is the definition of seafood opulence and a true French bistro classic. It is made with tender chunks of sweet lobster meat enveloped in a velvety, brandy-infused Béchamel sauce, returned to the shell, and topped with bubbling golden cheese. The brilliance of this recipe (and James’s signature twist) is the addition of both Dijon and English mustard, plus a generous splash of brandy, which cuts through the richness of the cream and creates a complex, savory gratin that is designed to impress.
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Why You Will Love This Lobster Thermidor Recipe:
- The “Wow” Factor: Serving the lobster meat inside the vibrant red shell makes for a spectacular centerpiece for a romantic dinner or celebration.
- Incredible Flavor Balance: The sharp mustard and boozy brandy prevent the rich cheese sauce from becoming too heavy or cloying.
- Make-Ahead Friendly: You can prepare the filling, stuff the shells, and keep them in the fridge for several hours before simply sliding them under the grill to finish.
- Textural Perfection: The contrast between the soft, sweet meat, the creamy sauce, and the crispy gratinated crust is unmatched.
James Martin Lobster Thermidor Ingredients
The Star:
- 2 x 750g Whole Lobsters
The Sauce Base:
- 50g Unsalted butter
- 50g Plain flour
- 300ml Whole milk
- 100ml Double cream
The Aromatics & Flavor:
- 1 Shallot
- 50ml Dry white wine
- Splash of Brandy or Cognac
- 1 tsp Dijon mustard
- 1 tsp English mustard
- Fresh herbs
The Topping:
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Check Price: £12.50 »- 50g Gruyère cheese: Grated (The classic melting cheese).
- 25g Parmesan
How To Make James Martin Lobster Thermidor
- Prep the Lobster: Place the cooked lobster on a board. Using a large, sharp knife, cut it in half lengthwise from head to tail. Remove the stomach sac (behind the head) and the dark intestinal tract. Remove the tail meat and claw meat, chop it into chunky bite-sized pieces, and set aside. Wash and dry the empty shells.
- The Flavor Base: In a saucepan, melt a knob of butter. Add the diced shallot and cook gently until soft. Turn up the heat, pour in the wine and brandy, and boil rapidly until the liquid has reduced by half. Remove from the pan and set aside.
- Make the Sauce: In the same pan, melt the 50g butter. Stir in the flour and cook for 2 minutes (a roux). Gradually whisk in the warm milk until you have a smooth, thick white sauce. Simmer for 3 minutes to cook out the flour taste.
- Enrich: Stir in the double cream, the reduced shallot/brandy mixture, the mustards, and half of the cheese. Stir until smooth and thick.
- Assemble: Fold the chopped lobster meat and fresh herbs into the sauce. (Do not cook it, just coat it). Spoon the mixture generously back into the clean lobster shells.
- The Topping: Sprinkle the remaining Gruyère and Parmesan over the stuffed shells.
- Grill: Place the lobsters on a baking tray and place under a hot grill (broiler) for 3 to 5 minutes.
- Serve: Remove when the cheese is bubbling and golden brown.
Recipe Tips
- Don’t Overcook: Since the lobster is already cooked, you are only warming it up. If you leave it under the grill too long, the meat will turn rubbery.
- Stabilize the Shells: If the rounded shells roll around on the baking tray, scrunch up a little aluminum foil and place it underneath them to hold them steady.
- Cheese Choice: Don’t skip the Gruyère. Cheddar is too oily; Gruyère has the perfect nutty flavor and melting point for this dish.
- The Brandy: If you don’t have brandy, you can use whisky, but brandy provides the traditional sweetness associated with Thermidor.
What To Serve With Lobster Thermidor?
James Martin stays true to the French bistro classic by serving Lobster Thermidor with thin, crispy French fries (pommes allumettes) or new potatoes. To balance the intense richness of the cheese and brandy sauce, a fresh green salad of bitter leaves like watercress or rocket with a sharp lemon vinaigrette is essential. Add a basket of warm, crusty bread to mop up the incredible sauce, and pair the meal with a chilled glass of Champagne or a buttery Chardonnay.
How To Store Leftovers Lobster Thermidor?
Safety Tip: Seafood spoils very quickly. If the dish has been sitting out at room temperature for more than 2 hours during dinner, it is safer to discard the leftovers rather than risk food poisoning.
- Refrigerator: Remove the lobster meat and sauce from the shell (if possible) and place it in an airtight container. It will keep for up to 2 days. If keeping it in the shell, wrap the entire shell tightly in cling film.
- Freezer: Freezing is not recommended. The creamy, cheese-based sauce often splits and becomes grainy upon thawing, and the delicate lobster meat will turn tough and rubbery.
How To Reheat Leftovers Lobster Thermidor?
Avoid the Microwave: It is strongly advised not to microwave this dish. The intense heat will cause the dairy sauce to split (separate into oil and lumps) and turn the delicate lobster meat tough and rubbery instantly.
- Low Oven (Recommended): Preheat your oven to 150°C (300°F). Place the lobster (in the shell or a dish) on a baking tray and cover loosely with foil to keep the moisture in. Heat for 10–15 minutes until just hot throughout.
- Stovetop (Meat Only): If the meat has been removed from the shell, place it in a saucepan over very low heat. Add a tiny splash of milk or cream to stop the sauce from splitting and stir gently until warm.
FAQs
Yes, frozen lobster tails or whole lobsters work well. Ensure they are thawed completely in the fridge overnight before cooking. Drain any excess water before adding the meat to the sauce to prevent it from becoming watery.
Yes, you can omit the brandy and wine. Replace the liquid volume with a little extra fish stock or chicken stock and a squeeze of lemon juice. The flavor won’t be as deep or authentic, but it will still be delicious.
Yes, this is a great dinner party trick. You can make the sauce, mix in the meat, stuff the shells, and sprinkle with cheese up to 6 hours ahead. Keep them covered in the fridge, then simply grill them when your guests arrive (add 2–3 minutes to the cooking time if chilling).
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Lobster Thermidor Nutrition Facts
- Calories: ~650 kcal
- Total Fat: 45g
- Saturated Fat: 25g
- Cholesterol: 180mg
- Sodium: 850mg
- Total Carbohydrate: 15g
- Protein: 35g
James Martin Lobster Thermidor
Course: Main, Lunch, DinnerCuisine: French, BrittishDifficulty: Easy2
servings30
minutes5
minutes650
kcalJames Martin Lobster Thermidor is a luxurious classic. Lobster meat in a rich brandy and mustard cheese sauce, gratinated in the shell. The ultimate celebratory meal.
Ingredients
- The Star:
2 x 750g Whole Lobsters
- The Sauce Base:
50g Unsalted butter
50g Plain flour
300ml Whole milk
100ml Double cream
- The Aromatics & Flavor:
1 Shallot
50ml Dry white wine
Splash of Brandy or Cognac
1 tsp Dijon mustard
1 tsp English mustard
Fresh herbs
- The Topping:
50g Gruyère cheese: Grated (The classic melting cheese).
25g Parmesan
Directions
- Prep the Lobster: Place the cooked lobster on a board. Using a large, sharp knife, cut it in half lengthwise from head to tail. Remove the stomach sac (behind the head) and the dark intestinal tract. Remove the tail meat and claw meat, chop it into chunky bite-sized pieces, and set aside. Wash and dry the empty shells.
- The Flavor Base: In a saucepan, melt a knob of butter. Add the diced shallot and cook gently until soft. Turn up the heat, pour in the wine and brandy, and boil rapidly until the liquid has reduced by half. Remove from the pan and set aside.
- Make the Sauce: In the same pan, melt the 50g butter. Stir in the flour and cook for 2 minutes (a roux). Gradually whisk in the warm milk until you have a smooth, thick white sauce. Simmer for 3 minutes to cook out the flour taste.
- Enrich: Stir in the double cream, the reduced shallot/brandy mixture, the mustards, and half of the cheese. Stir until smooth and thick.
- Assemble: Fold the chopped lobster meat and fresh herbs into the sauce. (Do not cook it, just coat it). Spoon the mixture generously back into the clean lobster shells.
- The Topping: Sprinkle the remaining Gruyère and Parmesan over the stuffed shells.
- Grill: Place the lobsters on a baking tray and place under a hot grill (broiler) for 3 to 5 minutes.
- Serve: Remove when the cheese is bubbling and golden brown.
Notes
- Don’t Overcook: Since the lobster is already cooked, you are only warming it up. If you leave it under the grill too long, the meat will turn rubbery.
Stabilize the Shells: If the rounded shells roll around on the baking tray, scrunch up a little aluminum foil and place it underneath them to hold them steady.
Cheese Choice: Don’t skip the Gruyère. Cheddar is too oily; Gruyère has the perfect nutty flavor and melting point for this dish.
The Brandy: If you don’t have brandy, you can use whisky, but brandy provides the traditional sweetness associated with Thermidor.
