Go Back
+ servings
Learn to make Julia Child's Lobster Thermidor recipe. A creamy and decadent lobster dish with white wine, mushrooms and splash of cognac.
Print Recipe
4.2 from 10 votes

Julia Child’s Lobster Thermidor Recipe

Learn to make Julia Child's Lobster Thermidor recipe. A creamy and decadent lobster dish with white wine, mushrooms and splash of cognac.
Prep Time20 mins
Cook Time1 hr 30 mins
Total Time1 hr 50 mins
Course: Main Course
Cuisine: French
Keyword: lobster thermidor recipe, lobster thermidor sauce, traditional lobster thermidor recipe, What to serve with lobster thermidor
Servings: 4
Calories: 606kcal
Author: Samantha Ferraro


Lobster Stock:

  • 3 cups white wine
  • 2 cups water
  • 1 large onion cut in quarters
  • 1 medium carrot cut in quarters
  • 1 stalk celery cut in quarters
  • Small bunch of parsley
  • 1 bay leaf
  • 1/4 tsp. thyme
  • 6 peppercorns
  • 1 Tbsp. fresh or dried tarragon
  • 2 live lobsters 2 pounds each


  • 1/2 pound sliced fresh mushrooms
  • Tbsp. butter
  • 1 tsp. lemon juice
  • 1/4 tsp. salt


  • 5 Tb. butter + 4 Tb butter separated
  • 6 Tbsp. flour
  • 1 Tbsp. cream + 1/2 c cream separated
  • 1 Tbsp. dry mustard
  • 2 egg yolks
  • Pinch cayenne pepper
  • 1/3 cup cognac
  • 1/2 cup grated Parmesan or Swiss cheese


Steaming the lobsters:

  • In a large pot (that will fit 2 large lobsters), simmer wine, water, vegetables, herbs, and seasonings for 15 minutes. Then bring to a rolling boil and add the live lobsters. Cover and boil for about 20 minutes or until the lobsters are done and turn bright red.
  • While the lobsters are steaming, stew the mushrooms slowly in a pan with the 1Tb butter, lemon juice, and salt for about 10 minutes until then begin to soften.

The sauce:

  • When the lobsters are done, remove them from the pot and put over ice. We filled our sink with ice and put the lobsters right in to cool down.
  • Save the mushroom cooking liquid and add that to the lobster stock. Bring to a boil until it has reduced to about 2 cups. (This is amazing lobster stock). Strain the stock through a sieve and discard vegetables and herbs and allow stock to stay at a simmer.
  • In another pot, cook 5 Tb butter and 6 Tb flour slowly for 2 minutes without browning.Take off heat and whisk in the lobster stock. Bring to a boil while whisking for 1 minute until it gets thick. Take off heat and whisk in 1 Tb heavy cream. Set aside.
  • In another bowl, whisk together the egg yolks, dry mustard, 1/2 c heavy cream and pinch of cayenne. Add the reserved cream mixture (that is sitting on the stove) to the egg mixture. Add it slowly while whisking and then return sauce to the pan. Stir the sauce every so often with a wooden spoon. Bring sauce to a boil for 2 minutes and then simmer. You want the sauce thick enough to coat the back of the wooden spoon. Taste for seasoning.

Sauteing the lobster meat:

  • Split the lobsters in half lengthwise, keeping the shell halves intact and remove the meat from the lobster tails and claws, and cut it into 1/2 inch pieces. Clean the lobster shells well and dry them. Reserve shells.
  • In another pan, saute lobster meat with 4Tb butter for about 5 minutes until the lobster meats turns a dark rosy color. Pour in cognac carefully and bring to a boil to cook off alcohol while shaking the pan. The liquid should reduce.

Final assembly:

  • Preheat oven to 425 degrees.In a large pan or bowl, mix together the mushrooms, lobster sauce and lobster meat.
  • On a baking sheet, place the 4 lobster shell halves down and wrap the bottom part of the shell with tin foil. This will help them the shelves stay in place.
  • Use the wooden spoon to scoop the lobster mixture into the shells. Don't over fill. Sprinkle with grated Parmesan cheese on top and place in upper 1/3 of oven. Allow to cook for 10-15 minutes until the top begins to brown.


Calories: 606kcal | Carbohydrates: 31g | Protein: 23g | Fat: 24g | Saturated Fat: 13g | Cholesterol: 230mg | Sodium: 757mg | Potassium: 706mg | Fiber: 2g | Sugar: 5g | Vitamin A: 3460IU | Vitamin C: 7.2mg | Calcium: 303mg | Iron: 4mg