Entree: Guernsey – Guernsey Lobster Thermidor (Classic baked lobster in a creamy mustard-cognac sauce, gratinéed with cheese)

Food safety reminder: Follow safe food-handling practices and use a food thermometer to verify safe internal cooking temperatures.

Serving Size: 4

Approximate Time

Prep 20 min

Cook 8 min

Total 28 min

Ingredients

U.S. measurements first, metric equivalents in parentheses. Conversions are approximate; oz means weight ounces, not fluid ounces.

- 2 whole cooked lobsters, approx. 1 1/4 lb (570 g) each
- 2 tbsp (30 g) unsalted butter
- 1 tbsp (15 ml) olive oil
- 1 small shallot, finely minced (about 1 oz (30 g))
- 4 oz (115 g) cremini or button mushrooms, sliced
- 2 tbsp (30 ml) cognac or brandy
- 1 cup (240 ml) heavy cream
- 1 tsp (5 g) Dijon mustard
- 1 large egg yolk
- 1/2 cup (50 g) grated Gruyère cheese, divided
- 1 tbsp (15 ml) lemon juice
- 2 tbsp (30 g) fine dry breadcrumbs
- 2 tbsp (30 ml) chopped fresh parsley
- Salt and freshly ground black pepper to taste
- Lemon wedges for serving

Show original ingredient measurements

- 2 whole cooked lobsters, approx. 1 1/4 lb (570 g) each
- 2 tbsp (30 g) unsalted butter
- 1 tbsp (15 ml) olive oil
- 1 small shallot, finely minced (about 1 oz / 30 g)
- 4 oz (115 g) cremini or button mushrooms, sliced
- 2 tbsp (30 ml) cognac or brandy
- 1 cup (240 ml) heavy cream
- 1 tsp (5 g) Dijon mustard
- 1 large egg yolk
- 1/2 cup (50 g) grated Gruyère cheese, divided
- 1 tbsp (15 ml) lemon juice
- 2 tbsp (30 g) fine dry breadcrumbs
- 2 tbsp (30 ml) chopped fresh parsley
- Salt and freshly ground black pepper to taste
- Lemon wedges for serving

Instructions

U.S. measurements first, metric equivalents in parentheses. Conversions are approximate.

1. If starting with live lobsters, bring a large pot of salted water to a rolling boil and submerge lobsters for 8–10 minutes until shells turn bright red. Remove and cool until safe to handle. If using already cooked lobsters, proceed to step 2.
2. Split each lobster lengthwise and remove the meat from the tails and claws, keeping the shells for stuffing. Chop the lobster meat into large bite-sized pieces and set aside.
3. In a sauté pan over medium heat, melt butter with olive oil. Add minced shallot and cook until translucent, about 2 minutes. Add sliced mushrooms and sauté until they release their liquid and begin to brown, about 4–5 minutes.
4. Carefully add cognac and, if desired, flambé to burn off alcohol (tilt pan away from face) or simmer 1 minute to reduce. Add heavy cream and Dijon mustard, stirring to combine. Simmer gently until the sauce thickens slightly, about 4–6 minutes.
5. Remove pan from heat and temper in the egg yolk by whisking a small spoonful of hot sauce into the yolk, then whisking the yolk mixture back into the sauce. Stir in 1/4 cup (25 g) grated Gruyère, lemon juice, chopped parsley, and season with salt and pepper.
6. Fold the chopped lobster meat into the sauce, then spoon the mixture back into the reserved lobster shells. Sprinkle the tops with remaining 1/4 cup (25 g) grated Gruyère and the breadcrumbs.
7. Place stuffed shells on a baking sheet and broil 3–5 inches (7.62 to 12.7 cm) from the heat until the topping is bubbling and golden brown, about 3–5 minutes. Watch closely to avoid burning.
8. Serve immediately with lemon wedges and a sprinkle of extra parsley.

1. If starting with live lobsters, bring a large pot of salted water to a rolling boil and submerge lobsters for 8–10 minutes until shells turn bright red. Remove and cool until safe to handle. If using already cooked lobsters, proceed to step 2.
2. Split each lobster lengthwise and remove the meat from the tails and claws, keeping the shells for stuffing. Chop the lobster meat into large bite-sized pieces and set aside.
3. In a sauté pan over medium heat, melt butter with olive oil. Add minced shallot and cook until translucent, about 2 minutes. Add sliced mushrooms and sauté until they release their liquid and begin to brown, about 4–5 minutes.
4. Carefully add cognac and, if desired, flambé to burn off alcohol (tilt pan away from face) or simmer 1 minute to reduce. Add heavy cream and Dijon mustard, stirring to combine. Simmer gently until the sauce thickens slightly, about 4–6 minutes.
5. Remove pan from heat and temper in the egg yolk by whisking a small spoonful of hot sauce into the yolk, then whisking the yolk mixture back into the sauce. Stir in 1/4 cup (25 g) grated Gruyère, lemon juice, chopped parsley, and season with salt and pepper.
6. Fold the chopped lobster meat into the sauce, then spoon the mixture back into the reserved lobster shells. Sprinkle the tops with remaining 1/4 cup (25 g) grated Gruyère and the breadcrumbs.
7. Place stuffed shells on a baking sheet and broil 3–5 inches from the heat until the topping is bubbling and golden brown, about 3–5 minutes. Watch closely to avoid burning.
8. Serve immediately with lemon wedges and a sprinkle of extra parsley.