Roast lamb with fresh mint topping, sticky roasted onions, gravy and crispy potatoes
I love cooking lamb at Christmas – why wouldn’t you when NZ lamb is the best you can get anywhere in the world? Even though it’s a roast, I’ve freshened it up so it suits a festive kiwi summer feast – lots of fresh herbs and a nice zingy dressing. And the mint and springy-onion garnish tops it off! Of course, I’ve still included a beautiful gravy and my ‘world famous in NZ’ crispy potatoes for those who want them (highly recommended.) This meal is perfect with a salad, and best finished off with one of my delicious desserts (click here to see them).
Prep time: 35mins, plus overnight for marinating if possible
Cooking time: 2 hours, plus resting
Skill level: Easy peasy! It may look like a lot of writing below, but it’s just me explaining things in detail to make it clear and easy to understand. It’s really just a fancy-looking meal made up of several simple components anyone can make.
Ingredients
Lamb
1 Quality Mark whole lamb leg, bone-in
1 bag French (or pickling) onions, peeled
2 cups chicken stock (for the gravy)
¼ cup flour (for the gravy)
Marinade
5 cloves garlic, crushed
2 tablespoons Dijon mustard
4 anchovy fillets, finely chopped
½ cup fresh rosemary, finely chopped
2 tablespoons dried marjoram
Zest of 2 lemons
2 tablespoons butter, softened
1 tablespoon lemon juice
3 tablespoons olive oil
Fresh mint topping
¾ cup crème fraiche
1 bunch fresh mint, leaves picked
1 clove garlic, crushed
2 tablespoons olive oil
1 tablespoon red or white wine vinegar, or lemon juice
Springy garnish
2-3 spring onions, opened out and sliced into very thin long strips
1 bunch fresh mint, leaves picked
Method
THE DAY BEFORE (if possible)
Place the lamb leg fat-side up on a clean chopping board and pat dry with a paper towel. Using a sharp knife, make a series of shallow cuts into the lamb a few cm apart, so the marinade flavours can really get in there.
Combine the marinade ingredients together and spread over the lamb, rubbing it into the cuts. Wrap the lamb in clingfilm and refrigerate, preferably overnight or for at least 2 hours.
ON THE DAY
Lamb
Remove the marinated lamb from the fridge 30 minutes before cooking. Preheat the oven to 180c (or 170c fan bake). Place the lamb in a roasting dish fat side up and season with lots of salt and pepper. Transfer to the oven and bake uncovered for 25-30 mins per 500g for medium (or 20-25 mins per 500g for rare/medium-rare). Baste once of twice with the lovely oil and juices in the bottom of the pan.
With 1 hour remaining, add the onions to the roasting dish and shuffle them around to coat them with some oil from the bottom of the pan. Season them, and turn them over once while cooking.
Remove from the oven, transfer the lamb and onions to a wooden board/warm plate and cover loosely with foil. Leave to rest for 20-30 minutes.
Spring onion and mint garnish
While the lamb is cooking, submerge the sliced spring onions and mint leaves in a bowl filled with lots of ice and water. Leave in the fridge for at least an hour – the spring onions will then curl up into little springy coils which look very cool and summery as garnish. The thinner and longer you’ve cut them, the better! Keep adding more ice if you need to leave it in the fridge for a few hours. When you’re ready to serve, drain and rest on paper towels.
Fresh mint topping
Combine all ingredients in a food processor, mortar and pestle, or mince everything finely with a knife and mix well. Taste and season with salt and pepper. Keeps in the fridge for a couple of hours before serving.
Gravy
To make a rich gravy while the lamb rests, tip most of the fat from the lamb roasting dish, leaving the meat juices and all that good stuff on the bottom.
Combine the flour with 1/2 cup water and add to the roasting dish, with remaining meat juices, on the stovetop over a medium heat. Add chicken stock, stirring all the time with a wooden spoon, for about 5-10 minutes until thickened. Make sure you scrape all the caramelised meat juices and onion off the bottom to add flavour. Strain if you like before pouring into a jug.
To serve
Place the rested lamb on a platter or board and drizzle with the fresh mint topping. Garnish with the springy onions and mint. Arrange the sticky roasted onions around the lamb. Serve with the gravy and Chelsea’s crispy roast potatoes (click here for the recipe). This meal is lovely with even just some BBQ’d asparagus dressed with a little lemon zest, salt, pepper, avocado oil and fresh parsley. Or a nice salad (great recipe here) – or vegetables.