📝 About This Recipe
Named after the month in the French Republican Calendar in which it premiered at a Parisian theater in 1894, Homard Thermidor is the pinnacle of French coastal elegance. This decadent dish features succulent lobster meat bathed in a rich, velvety Cognac and Dijon mustard cream sauce, tucked back into its golden shell and gratinated to perfection. It is a masterclass in balancing the sweetness of fresh seafood with the complex, umami-rich depths of a classic Mornay-style reduction.
🥗 Ingredients
The Lobster
- 2 pieces Live Whole Lobsters (approx. 1.5 lbs each)
- 2 tablespoons Sea Salt (for the boiling water)
The Thermidor Sauce
- 4 tablespoons Unsalted Butter (high-quality European style preferred)
- 2 pieces Shallots (very finely minced)
- 1 tablespoon Fresh Tarragon (finely chopped)
- 1/4 cup Cognac or Brandy (plus 1 tablespoon for the meat)
- 1/2 cup Dry White Wine (such as Chablis or Muscadet)
- 1 cup Heavy Cream (at room temperature)
- 1.5 teaspoons Dijon Mustard (smooth, traditional French)
- 1 piece Egg Yolk (beaten, to thicken the sauce)
- 1 pinch Cayenne Pepper (for a subtle heat)
The Topping
- 1/2 cup Gruyère Cheese (freshly grated)
- 2 tablespoons Parmesan Cheese (finely grated)
- 1 tablespoon Fresh Parsley (chopped, for garnish)
👨🍳 Instructions
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1
Bring a very large pot of salted water to a rolling boil. Submerge the lobsters head-first and cook for 8-10 minutes. They should be bright red but slightly underdone, as they will cook further in the oven.
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2
Immediately transfer the lobsters to an ice bath to stop the cooking process. Once cool enough to handle, drain them thoroughly.
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3
Using a sharp chef's knife, split the lobsters in half lengthwise from head to tail. Remove and discard the sandy stomach sac behind the eyes and the dark intestinal vein.
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4
Carefully remove the meat from the tails and claws. Keep the four half-shells intact; rinse them and pat them dry for later use. Chop the lobster meat into bite-sized 1-inch chunks.
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5
In a medium skillet, melt 1 tablespoon of butter over medium heat. Sauté the lobster meat for 1-2 minutes with a splash of Cognac. Remove the meat and set aside, reserving any juices.
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6
In the same skillet, melt the remaining 3 tablespoons of butter. Add the minced shallots and cook until translucent and soft, about 3 minutes.
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7
Pour in the white wine and the 1/4 cup of Cognac. Increase heat to medium-high and simmer until the liquid has reduced by half.
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8
Whisk in the heavy cream and simmer gently for 5-7 minutes until the sauce thickens enough to coat the back of a spoon.
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9
Lower the heat to its minimum setting. Whisk in the Dijon mustard, tarragon, and cayenne pepper. Taste and adjust seasoning with salt and white pepper.
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10
Temper the egg yolk by whisking a spoonful of the hot sauce into it, then slowly whisk the mixture back into the main skillet. Do not let it boil, or the egg will curdle.
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11
Fold the cooked lobster meat back into the cream sauce until well coated. Preheat your oven's broiler to high.
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12
Place the empty lobster shells on a baking sheet. Spoon the lobster and sauce mixture generously into the tail and head cavities of the shells.
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13
Sprinkle the grated Gruyère and Parmesan evenly over the top of the filling.
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14
Place under the broiler for 3-5 minutes, watching closely, until the cheese is bubbling and develops deep golden-brown spots.
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15
Remove from the oven, garnish with fresh parsley, and serve immediately while piping hot.
💡 Chef's Tips
Always use fresh, live lobsters for the best texture; frozen lobster can become rubbery when double-cooked. When reducing the cream, be patient—a slow reduction creates a much silkier mouthfeel than using a thickener like flour. If you are nervous about the lobster shells moving on the tray, create small 'nests' out of crumpled aluminum foil or rock salt to keep them level. Don't skip the tarragon; its subtle anise flavor is the secret ingredient that defines a true Thermidor sauce. Ensure the mustard is whisked in at the end to preserve its bright, piquant flavor profile.
🍽️ Serving Suggestions
Pair with a crisp, chilled glass of Puligny-Montrachet or a high-quality dry Champagne. Serve alongside buttery steamed asparagus or haricots verts with toasted almonds. A side of fragrant Jasmine rice or crusty French baguette is essential for soaking up the extra sauce. Follow this rich meal with a light lemon sorbet to cleanse the palate. For a classic presentation, serve on a bed of fresh watercress or rock salt.