Roast Lamb Rump
Roast lamb rump gives you a small joint with a crisp fat cap and a pink centre in under an hour. Each rump is scored, seasoned and seared fat-side down in an ovenproof pan, then roasted at 200°C (180°C fan), gas 6, for 15 minutes with garlic and rosemary. It serves two and is far quicker than a full leg of lamb.
- Total
- 51 min
- Prep
- 10 min
- Cook
- 21 min
- Serves
- 2
- Per serving
- 520kcal
Keeping roast lamb rump juicy
A lamb rump is a tender muscle with a layer of fat on top, so the order of cooking matters. Rendering the fat in the pan first gives a crisp, golden cap and leaves less fat on the plate. The oven then finishes the meat gently, with no further browning needed.
The thermometer is the surest guide. Rumps differ in thickness, and a thick 300g piece needs longer than a flat 200g one. Pull the lamb out 3°C before the target temperature, as it carries on cooking during the rest.
Method for roast lamb rump
Tap a time to start a timer.
- Prepare the lamb Take the lamb out of the fridge before cooking. Heat the oven to 200°C (180°C fan), gas 6. Pat the rumps dry with kitchen paper and score the fat in a diamond pattern, cutting through the fat but not into the meat. Rub the salt and pepper into the fat and over the meat.
- Sear the fat side Heat the oil in the ovenproof pan over a medium heat. Lay the rumps in fat-side down and cook for , until the fat is golden and has rendered. Turn them with tongs and brown the other side for .
- Add the aromatics Add the garlic and rosemary to the pan for the final 30 seconds.
- Roast Put the pan in the oven and roast for for medium-rare (55°C) or for medium (60°C), measuring in the thickest part with a thermometer. A larger rump may need a few extra minutes.
- Rest Move the lamb to a board, cover loosely with foil and rest for . The temperature will rise by 2–3°C and the meat will carve cleanly.
- Carve Slice the lamb across the grain into thick slices and spoon over the juices from the pan.
What to serve with roast lamb rump
Roast potatoes and seasonal vegetables are the classic partners, along with mint sauce. If you are cooking for a crowd, the same flavours work on a roast leg of lamb. Without a free oven, you can use the air fryer lamb rump roast method instead.
Common problems and fixes for Roast Lamb Rump
- The fat is not crisp.
- The pan was not hot enough or the fat was damp. Pat the fat dry, score it deeply, and render it fat-side down for the full 4–5 minutes before the lamb goes in the oven.
- The meat is grey and tough.
- It roasted too long. Check from 10 minutes and take it out about 3°C below your target temperature, because it keeps cooking while it rests.
- The juices run out when you slice it.
- It was carved straight away. Rest it for the full 10 minutes before slicing.
Frequently asked questions about Roast Lamb Rump
How long do you roast lamb rump for?
12 minutes at 200°C (180°C fan), gas 6, after searing, for medium-rare, and 15 minutes for medium. This is for rumps of about 250g.
What temperature should lamb rump be?
55°C for medium-rare, 60°C for medium and 70°C or above for well done. Whole cuts of lamb can be served pink, but the outside must be well browned.
Can you cook lamb rump ahead of time?
You can season it a few hours ahead and keep it covered in the fridge, but cook it fresh. Reheated lamb goes tough.
What goes well with roast lamb rump?
Roast potatoes, buttered carrots and green beans are traditional, with mint sauce on the side. Redcurrant jelly or a red wine gravy also work.
How did you like the recipe?
4.9 / 5 · 6 ratings
