Classic Lobster Thermidor with a Rich and Creamy Sauce 🇫🇷

Lobster Thermidor is a classic French dish featuring lobster meat in a rich, creamy sauce, flavoured with mustard and cognac, topped with Comté cheese, and grilled in the lobster shell.

Lobster Thermidor Origins

This dish was created in the 1880s by the renowned French chef Auguste Escoffier while working at La Maison Maire, a prestigious restaurant in Paris. This iconic dish was named after the play Thermidor by the famous French playwright Victorien Sardou. The play was first performed in 1891. Although initially controversial, it later gained popularity in 1896. To mark the play’s success, Paillard, the restaurant owner where Escoffier worked, named the new lobster dish Lobster Thermidor in tribute.

However, there are alternative theories regarding the origin of Lobster Thermidor. One such theory credits Léopold Étienne Mourier, a French chef, with creating the dish for the opening of the Thermidor play in 1891. Mourier was known for his innovative cooking, and some sources suggest that he, rather than Escoffier, originally named the dish after the play.

Regardless of who created Lobster Thermidor, one thing is certain: the play Thermidor had a significant role in naming the dish.

Classic Lobster Thermidor Ingredients

In Pellaprat’s book, the ingredients listed for Lobster Thermidor include Béchamel sauce and Bercy sauce (made from Velouté sauce, among other components), making it rather complex, with a mixture of all the mighty French sauces. To keep things simple, here’s the full list of ingredients.

Some versions of Lobster Thermidor include tarragon and mushrooms as ingredients, but since I’m following the traditional recipe from the book, I didn’t include them, but you can play around.

• lobster – Buy live lobster for the freshest flavour, you can also substitute with langoustines or other large crustaceans for a similar luxurious experience.
• onion – Use standard yellow onions, this is for lobster broth.
• shallots – They have a delicate, slightly sweet flavour and do not overpower the sauce.
• white wine – Use a dry white wine of your choice.
• double cream
• butter – Unsalted.
• cognac – Cognac is traditionally used in this dish, but you can substitute it with brandy.
• flour – Plain white, or all-purpose flour.
• milk – Full fat or semi-skimmed.
• fish stock – Use lobster broth.
• mustard – Use Dijon or English mustard.
• nutmeg – Although the amount of nutmeg may seem small, it is a crucial ingredient in Lobster Thermidor. Its rich, aromatic flavour adds a distinctive depth to the sauce.

Optional: parsley, tarragon, mushrooms

🐟 While you’re here, check out these yummy seafood dishes from around the world:

Monégasque Seafood & Fish Pie 🦐🦪
French Mussels Provencal in Tomato Sauce 🦪🍅
Mediterranean Stuffed Squid in Tomato Sauce 🦑🍅

How to prepare Lobster Thermidor

1. Cook the lobster

I’ve come across some recipes that call for live lobsters to be cut in half without boiling them first. Not only is this far from traditional, but I’ve no idea who “invented” such a method – it certainly doesn’t sound pleasant, nor does it align with classic culinary practices.

• Fill a large pot with water. Add the onion cut into quarters, lemon sliced into wedges, some parsley, and bay leaf.
• Once it starts to boil, drop in your lobster. Let it cook for about 8-10 minutes.
• When it’s done, immediately transfer it to a bowl of cold water to stop the cooking process.

2. Prepare the Thermidor sauce

• Finely chop the onion, ensuring it is very finely diced, and sauté it gently in butter over low heat for a few minutes, being careful not to let it brown. Once softened, add white wine and cook the onion until completely tender.
• Next, sprinkle in the flour and cook for 30 seconds, then gradually pour in hot milk, stirring constantly to form a smooth roux. Add a pinch of nutmeg to flavour the sauce.
• Add fish stock, or use the water from cooking the lobster. Finish with a splash of double cream, cooking gently over low heat for a minute or two. If the sauce becomes too thick, adjust with a little extra milk.
• Once the desired consistency is reached, remove the pan from the heat and stir in mustard and cognac. Your sauce is now ready. Don’t worry about the alcohol in the cognac; it will evaporate during the grilling process.

📝 At this stage, you may add tarragon, parsley, or chives if desired, as these herbs are commonly included in more modern versions of Thermidor.

3. Prepare the meat

• Cut the cooked lobster in half lengthways, carefully removing the meat from the tail and body. I didn’t remove the meat from the claws; instead, I cracked them open for easy access.
• Chop the lobster meat into small chunks and place it into a bowl. Add the sauce one tablespoon at a time, stirring gently, and continue adding the sauce until you reach the desired consistency.
• Stuff each lobster half with lobster meat and sauce mixture, then top it with grated cheese.

📝In the original recipe, the cooked lobster meat is removed from the claws, chopped into small cubes, and mixed with two tablespoons of sauce before being placed back into the lobster shell. Slice the tail meat into medallions and arrange them on top. Pour the sauce over the lobster, sprinkle with grated cheese, and drizzle with melted butter before grilling.

Grill the lobster in the oven at 180°C for 5-7 minutes, or until the cheese is melted and golden. Enjoy your Classic Lobster Thermidor.

Serving Lobster Thermidor

Lobster Thermidor can be served as an elegant starter, hot entrée, or a luxurious main course.

As if the richness of Lobster Thermidor wasn’t indulgent enough, I went all out and served it with three decadent French side dishes; thyme-infused mushroom and leek rice in ramekin, a classic Gratin Dauphinois (potato and cheese gratin), and crispy bacon and onion roast potatoes. I also served a refreshing lamb’s lettuce salad and a vibrant sauce verte on the side.

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