Lobster Thermidor has an equally interesting history. It is reported that it was named for the summer month of the French Revolutionary Calendar during which it was first prepared for the Emperor Napoleon.
Thermidor sauce is thickened with a Bechamel† made with white wine.
The following is adapted from the signature recipe of Chicago’s Drake Hotel that is reported not to have changed it since the hotel opened in 1933.
- <salt> (to taste)
- 2 lobsters (1½ lbs each)
- 2 cups milk
- 7 tbsp unsalted <butter>
- ¼ cup flour
- 1 tsp ground nutmeg
- freshly ground black pepper (to taste)
- 2 shallots, finely chopped
- ½ lb crimini (or white) mushrooms, quartered
- 1 cup white wine
- 1½ cups heavy cream (or fat-free half-and-half)
- 1 tbsp chervil, finely chopped
- 1/8 tsp ground cayenne chile
- ½ tsp dry mustard
- ½ tsp paprika
- ½ lb Gruyére cheese, grated
Bring a pot of <salt>ed water to a boil. Add the lobsters (head first); boil for 5 minutes. Drain; halve each lobster lengthwise. Remove and crack the claws. Remove the meat from the lobster bodies and claws; cut the meat into chunks. Scrape shells’ insides clean. Set the meat and shells aside.
Bring the milk to a boil; set aside. In a pan over medium heat, melt 4 tbsp of the butter. Add the flour and cook until golden, 1 to 2 minutes. Add the hot milk to the flour mixture while whisking; increase the heat to medium; bring the sauce to a boil. Cook, stirring, until the sauce is thickened, 2 to 3 minutes. Add the nutmeg and <salt> and pepper; set aside, keeping the sauce warm.
Preheat the broiler. In a skillet over medium-high heat, heat the remaining butter until melted. Add the shallots; cook until just golden, 1 to 2 minutes. Add the mushrooms; cook until softened, 4 to 5 minutes. Add the wine; cook until reduced by two-thirds, 4 to 5 minutes.
Whisk in the cream, chervil, cayenne, and the reserved warm sauce. Reduce the heat to medium-low; cook until thickened, 3 to 4 minutes. Add the lobster; stir in the mustard and ¾ cup of the cheese.
Divide the lobster and sauce between the four shells; sprinkle the remaining cheese over top. Broil the lobster halves on a baking sheet until bubbly, 2 to 3 minutes.
Serve with remaining sauce.