📝 About This Recipe
Originally created in 1894 at a Parisian brasserie to celebrate the opening of a play, Lobster Thermidor remains the ultimate expression of French culinary luxury. This decadent dish features succulent lobster meat bathed in a rich, velvety Cognac-infused Mornay sauce, accented with dry mustard and fresh tarragon. Baked directly in the shell until golden and bubbling, it offers a sophisticated harmony of sweet seafood and savory cream that defines fine dining at its best.
🥗 Ingredients
The Lobster
- 2 pieces Live Whole Lobsters (approximately 1.5 lbs each)
- 2 tablespoons Sea Salt (for the boiling water)
The Thermidor Sauce
- 4 tablespoons Unsalted Butter (high quality, divided)
- 2 Shallots (minced very finely)
- 1/2 cup Fresh Button Mushrooms (finely chopped)
- 1/4 cup Dry White Wine (such as Sauvignon Blanc or Muscadet)
- 2 tablespoons Cognac or Brandy (for deglazing)
- 2 tablespoons All-Purpose Flour
- 1 cup Whole Milk (warmed slightly)
- 1/4 cup Heavy Cream
- 1 teaspoon Dijon Mustard
- 1/2 teaspoon Dry English Mustard Powder
- 1 tablespoon Fresh Tarragon (finely chopped)
- 1 tablespoon Fresh Parsley (chopped)
- 1 pinch Cayenne Pepper
The Topping
- 1/2 cup Gruyère Cheese (freshly grated)
- 1 tablespoon Parmesan Cheese (finely grated)
- 1 pinch Paprika (for color)
👨🍳 Instructions
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1
Bring a large pot of salted water to a rolling boil. Submerge the lobsters head-first and cook for 8-10 minutes, just until they turn bright red (they will finish cooking in the oven).
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2
Immediately transfer lobsters to an ice bath to stop the cooking process. Once cooled, pat them dry.
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3
Using a sharp chef's knife, split the lobsters in half lengthwise from head to tail. Remove the meat from the tails and claws, discarding the intestinal vein and the gritty stomach sac near the head.
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4
Rinse the empty head and tail shells thoroughly and pat dry; place them on a parchment-lined baking sheet. Cut the lobster meat into bite-sized 1-inch chunks and set aside.
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5
In a medium saucepan, melt 2 tablespoons of butter over medium heat. Add the minced shallots and mushrooms, sautéing for 4-5 minutes until softened and the moisture has evaporated.
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6
Deglaze the pan with the Cognac and white wine. Simmer until the liquid has reduced by half, then transfer the mixture to a small bowl and set aside.
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7
In the same pan, melt the remaining 2 tablespoons of butter. Whisk in the flour to create a roux and cook for 1-2 minutes without browning.
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8
Slowly whisk in the warmed milk and heavy cream. Continue whisking over medium-low heat until the sauce thickens enough to coat the back of a spoon.
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9
Remove the sauce from heat. Stir in the Dijon mustard, mustard powder, cayenne, tarragon, parsley, and the sautéed mushroom/shallot mixture.
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10
Gently fold the lobster meat into the sauce. Taste and season with a little more salt if necessary.
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11
Spoon the lobster and sauce mixture generously back into the cleaned lobster shells.
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12
Combine the Gruyère and Parmesan cheeses and sprinkle evenly over the top of each lobster half. Dust with a tiny pinch of paprika.
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13
Place under a preheated broiler for 3-5 minutes, or until the cheese is golden-brown and bubbling. Watch closely to prevent burning.
💡 Chef's Tips
Always use fresh, high-quality Gruyère for the best melt and nutty flavor profile. Do not overcook the lobster during the initial boil; it should be slightly underdone so it remains tender after the broiler. If your sauce is too thick, add a tablespoon of milk at a time until the desired consistency is reached. Ensure the lobster shells are completely dry before stuffing to prevent the sauce from becoming watery. For an extra touch of luxury, add a teaspoon of truffle oil to the sauce just before folding in the lobster.
🍽️ Serving Suggestions
Serve with a crisp, chilled glass of Chablis or a vintage Champagne to cut through the richness. A side of buttery haricots verts (French green beans) provides a fresh, crunchy contrast. Serve alongside a simple bed of wild rice or buttered saffron rice to soak up the extra sauce. A light arugula salad with a lemon vinaigrette acts as a perfect palate cleanser. Warm, crusty baguette slices are essential for dipping into the remaining Mornay sauce.