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5 from 1 vote

Lobster Thermidor

Rich, elegant, creamy dish for a very special occasion. Haute cuisine at its best!

Ingredients

For the Lobster Stock:

  • 2 Tbsp. Vegetable oil or other neutral oil I used Olive Oil as that's what I had in the pantry.
  • 2 Large Shallots, peeled and sliced
  • 4 Medium Cloves garlic, smashed
  • 1 Celery rib, sliced
  • 2 Large Stalks fresh fennel The fennel was not in Alton's recipe, but added a very nice touch of sweetness.
  • Reserved Lobster/shrimp shells from 2 lobsters and a dozen shrimp
  • 1 Tbsp. Tomato paste
  • 1/4 cup Brandy
  • 1/4 cup Sherry Alton calls for one or the other. I used both.
  • 4 cups Water
  • 2 sprigs Tarragon Or 1/2 tsp. dried

For the Lobster Thermidor Sauce:

  • 2 1/2 Tbsp. Butter, salted
  • 1 Large Shallot, finely minced
  • 3 Tbsp. All-purpose flour
  • 1/8 tsp. Cayenne pepper Alton calls for 1/4 tsp.
  • 1/2 cup Heavy cream
  • 1 Tbsp. Dijon mustard
  • 1/4 cup Grated Gruyere cheese, plus more for sprinkling on top before baking
  • 2 Tbsp. Grated parmesan Also not in his original recipe.
  • 1 tsp. Dried tarragon
  • Salt and freshly ground black pepper, to taste
  • 2 Tbsp. Grated parmesan for sprinkling

Instructions

To kill, cook and prepare the Lobster:

  • On a work surface, kill each lobster by pressing the tip of a heavy chef's knife in the crack just behind the eyes in the center of the head pressing down to split the head in half.
  • Prepare an ice bath in a large bowl. Place a steamer insert in the bottom of a large lidded stock pot and add 1 inch of water. Bring to a boil over high heat, then steam the lobsters, covered until just cooked through, about 9 minutes. This shorter cooking time may not completely cook the tomalley or roe inside the lobsters, but will produce a more tender lobster. Immediately transfer the lobsters to the ice bath and let cool and 4 minutes.
  • As soon as the lobsters are cool, split the lobsters in half lengthwise through the middle. Using a spoon, gently remove any tomalley and roe, if present, and save for another use or discard. Remove the stomach (small sac located in the head behind the lobsters eyes) and discard.
  • Being careful not to break apart the halved lobster shells, remove the tail meat and transfer to a medium bowl. Carefully twist lobster claws and knuckles from bodies, again taking care not to break apart the body shells. Using kitchen shears, lobster crackers and/or the back of a heavy cleaver, crack claws and knuckles and remove meat, transferring it to the bowl with the lobster tails; transfer claw and knuckle shells to a bowl and set aside. These will be used to make the stock if you did not make it in advance. On a work surface, cut lobster meat into large chunks, then return to bowl. Cover lobster meat and transfer to the fridge.
  • Arrange the 4 lobster shell halves on a rimmed baking sheet; cover and refrigerate. Cut up the remaining shells and body of the smaller lobster and transfer to the bowl with the claw shells, which will be used for the stock.

For the Lobster stock:

  • In a large saucepan or 4-5 qt. Dutch oven, heat oil over medium heat until shimmering. Add shallots, garlic, celery, and fennel if using and cook, stirring often, until softened; about 3 minutes.
  • Add reserved lobster shells and cook, stirring, until the ingredients begin to brown on the bottom of the pot; about 4 minutes. Stir in tomato paste and cook for 1 minutes. Add brandy (and sherry if using) and cook, stirring and scraping the bottom of the pot, until some of the raw alcohol smell is gone; about 2 minutes. Add water, tarragon and cook, stirring occasionally until stock is flavorful and liquid is reduced by about half; about 20 minutes. My stock only reduced by 1/2 cup to make a total of 3 1/2 cups stock, but it was both flavorful and delicious!

For the Lobster Thermidor Sauce:

  • In a 2-3 qt. saute pan or saucier, melt butter over medium heat. Add shallot and cook, stirring until softened; about 3 minutes. Stir in flour and cayenne and cook until raw flour smell has cooked off; about 1 minutes.
  • Whisk in 1 cup reserved lobster stock adding it in small additions and whisking out lumps as you go to ensure a smooth, silky texture. Then whisk in cream and mustard. Add Gruyere (and parmesan if using) and cook, stirring or whisking constantly until fully melted. Remove from the heat. Stir in tarragon and season with salt and pepper to taste. Scrape thermidor sauce into a heatproof container, press plastic directly against its surface to prevent a skin from forming, and let cool in the refrigerator.
  • When ready to cook, position oven rack about 6 inches from broiler and heat broiler. Remove lobster meat from the fridge and drain any accumulated liquid. Stir cooled thermidor sauce into the lobster meat.
  • Mound dressed lobster meat into reserved shells along their entire length from tail to head. Sprinkle with additional grated Gruyere and parmesan cheese. I also sprinkled with a little more dried tarragon. Broil until heated through and browned on top. If surface browns before lobster meat is warmed through, switch off the broiler; turn the oven on to 350 degrees and continue to cook until warmed through; 5 to 7 minutes more.
  • Carefully transfer stuffed lobster shells to plates and serve with lemon wedges, if desired.

Notes

Alton suggests cooking a third, smaller lobster to add to the lobster mixture, but the two  1 1/2 lb. lobsters I used provided a very generous amount of lobster per shell. We are both big eaters, and HUGE lobster fans, but one stuffed lobster shell was more than sufficient for a serving.