Equipment
Ingredients
Lamb and Aromatics
- 2000 g bone-in leg of lamb, trimmed of excess surface fat
- 2 yellow onion, peeled and halved
- 3 carrots, roughly chopped
- 3 celery stalks, roughly chopped
- 4 garlic, smashed
- 5 g black peppercorns
- 2 bay leaves
- 10 g fresh thyme, whole sprigs
- 3000 ml water
- 15 g kosher salt
Lemon-Caper Sauce
- 50 g unsalted butter
- 50 g all-purpose flour
- 500 ml lamb cooking liquid, hot, reserved from boiling the lamb
- 60 g capers, drained and roughly chopped
- 30 ml lemon juice, freshly squeezed
- 50 ml heavy cream
- 10 g fresh parsley, finely chopped
- 2 g kosher salt
- 1 g black pepper
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 752 kcal
- Protein
- 66 g
- Carbohydrates
- 37 g
- Fat
- 38 g
- Fiber
- 9 g
- Sugar
- 15 g
- Sodium
- 1406 mg
- Saturated Fat
- 3 g
- Trans Fat
- 0 g
- Monounsaturated Fat
- 1 g
- Polyunsaturated Fat
- 0 g
- Cholesterol
- 13 mg
- Potassium
- 1013 mg
- Calcium
- 133 mg
- Iron
- 1.9 mg
- Magnesium
- 86 mg
- Phosphorus
- 131 mg
- Zinc
- 0.6 mg
- Vitamin A
- 1179 mcg
- Vitamin C
- 14 mg
- Vitamin E
- 2.0 mg
- Vitamin K
- 62 mcg
- Vitamin B6
- 0.4 mg
- Vitamin B12
- 0.0 mcg
- Thiamin
- 0.19 mg
- Riboflavin
- 0.16 mg
- Niacin
- 2.4 mg
- Folate
- 30 mcg
- Water
- 89 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Place the leg of lamb, onions, carrots, celery, garlic, peppercorns, bay leaves, thyme, and salt into a large stockpot. Pour in enough cold water to submerge the meat completely.
Place the stockpot over medium-high heat and bring just to a boil. Use a spoon to regularly skim off and discard any gray foam or impurities that rise to the surface.
Once boiling, immediately reduce the heat to low. Cover the pot partially and simmer gently for 1.5 to 2 hours. Ensure the internal temperature reaches 63°C/145°F at the thickest part for a medium-well finish.
Carefully lift the lamb from the broth and transfer it to a cutting board. Tent loosely with aluminum foil and let it rest for 20 minutes. Skim the fat from the top of the pot and carefully measure out 500ml of the hot cooking liquid for the sauce.
While the meat rests, melt the butter in a medium saucepan over medium heat. Add the flour and cook, stirring constantly with a whisk, for 2 minutes to cook off the raw flour taste without browning the roux.
Gradually whisk the reserved 500ml of hot lamb cooking liquid into the roux. Continue whisking constantly until the sauce comes to a gentle simmer and thickens smoothly.
Remove the saucepan from the heat. Stir in the chopped capers, lemon juice, heavy cream, and fresh parsley. Taste and season with additional salt and black pepper as needed.
Carve the rested leg of lamb into thick slices.
Arrange the sliced lamb on a warmed serving platter and spoon a generous amount of the hot lemon-caper sauce over the top. Serve the remaining sauce in a gravy boat alongside.
Chef's Notes
- Do not discard the remaining lamb cooking liquid. Strain it and freeze it; this incredibly rich stock makes an outstanding base for Scotch broth, barley soup, or winter vegetable stews.
- For maximum tenderness, temperature control is paramount. A rolling boil will inevitably result in chewy meat. Keep your heat minimal and patient.
- If your capers are large or mature, give them a rough chop to distribute their sharp, briny flavor more evenly throughout the sauce.
- The resting period is non-negotiable. Even though boiled meats are cooked in a moist environment, they still require time for the internal juices to redistribute and settle before slicing.
Storage
Refrigerator: 3 days — Store the meat and sauce in separate airtight containers. Retain extra cooking broth to keep the lamb moist.
Freezer: 2 months — Freeze meat submerged in its broth to prevent freezer burn. The cream-finished sauce may separate slightly upon thawing and should be gently reheated while whisking.
Reheating: Gently warm sliced lamb in a pan with a splash of broth. Reheat sauce separately over very low heat.
Troubleshooting
Lamb is tough, stringy, or dry
Cause: The liquid boiled too vigorously, causing the muscle fibers to seize up.
Fix: Slice the meat thinly across the grain and submerge the slices in the warm broth for 10 minutes to help them absorb moisture.
Prevention: Maintain a barely-there simmer with small bubbles occasionally breaking the surface.
Sauce is lumpy and uneven
Cause: The hot broth was added too quickly to the roux, or not whisked thoroughly.
Fix: Pass the sauce through a fine-mesh sieve or blend briefly with an immersion blender before adding the capers and parsley.
Prevention: Add the liquid in small, gradual splashes, whisking until smooth before adding more.
Sauce tastes overly salty
Cause: Capers were preserved in heavy salt and not adequately rinsed, or the cooking broth reduced too much.
Fix: Add a splash of additional heavy cream or a pinch of sugar to balance the saltiness.
Prevention: Always taste capers before adding. If heavily salted, rinse and soak them in fresh water for 15 minutes prior to chopping.
Cultural Context
Boiled mutton or lamb served with caper sauce is a quintessential piece of British culinary heritage, achieving wide popularity throughout the 19th century. The sharp, acidic tang of the capers and lemon was traditionally designed to cut through the notoriously rich, fatty profile of the meat. While roasting has become the dominant method today, simmering yields unparalleled tenderness and the economical bonus of deeply flavored stock.
