Name: Roast lamb with onion gravy
Prep time: 5 min
Cook time: 3 h 30 min
Total time: 3 h 45 min
Yield: 1
Cuisine: New Zealand
Ingredients: 2 onions; 2.5kg lamb leg; 1 Tbsp olive oil; ½ tsp sea salt; 1 Tbsp rosemary, chopped; 1 beef oxo cube; ½ cup boiling water; 2 Tbsp cornflour; 2 Tbsp water

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This traditional roast lamb is served with a delicious homemade onion gravy.

This is a recipe for one of my all-time favourite dinners - Roast Lamb. Growing up on a farm in Rotorua it was always special to have a Sunday roast. This recipe produces a delicious onion gravy which goes so well with the sliced lamb and roasted veggies.

We're so lucky to have such great quality lamb in our New Zealand supermarkets. Add in lots of fresh vegetables and you have the perfect roast. Below I have explained how to use any leftover meat to create a roast lamb pie.

I have kept my lamb recipe super simple and it is coated with olive oil, salt and rosemary. The meat sits on top of the onions so the juices from the roasting lamb create a delicious onion and lamb stock which I use to make homemade gravy from scratch.

I like to serve my roast lamb with lots of roast veggies. This time I've used potatoes, kumara, butternut pumpkin and of course mint jelly or sauce with some heated frozen peas.

If you have any left over lamb simply stir it through the gravy and freeze for later. Then you have a great last minute pie filling you can top with pastry or potato slices and bake until golden and piping hot. For another epic roast dinner, be sure to check out my Roast Pork with Gravy recipe.

How to make roast lamb:

First of all preheat you oven to 170°C fanbake. Cut onions into wedges and place them in the base of a oven-proof casserole or cast iron dish. Pour in the water and place the leg of lamb on top of the onions. Brush over olive oil then sprinkle over salt and rosemary. After 2 hours add an extra 1 cup of water to the base of the dish this stops the onions catching on the bottom of the pan.

Peel and chop your chosen veggies then coat in olive oil. Bake on a tray until golden and cooked through. I start my vegetables cooking 1-1.5 hours before serving. The potatoes take the longest to bake so chop them smaller than the pumpkin and kumara.

After 3-3.5 hours the lamb will be tender and the fat crispy (this will depend on the weight and size of your piece of meat). Remove it from the dish and cover in tinfoil to rest until serving.

Add the dish to the hob on the stovetop and bring it to a simmer. Pour in the stock and cornflour slurry. Simmer stirring until the gravy thickens up, this should only take a few minutes, double the cornflour slurry if needed.

Carve hot lamb and serve with onion gravy, roasted veggies, peas and mint sauce or jelly.

How to make a roast lamb pie:

Once dinner has been served, slice any extra lamb off the bone and cut it into small bite size pieces. Stir this through any leftover gravy then store in an airtight container in the freezer. When you are ready to bake your pie, thaw the pie filling in the fridge overnight.

Line a pie dish with baking paper and puff pastry, fill with the thawed roast lamb and gravy mix. Top with sliced potatoes sprinkled with salt and a little bit of parmesan cheese. Or you can top it with a simple pastry lid. Bake your pie for at least 30 minutes until the pastry is golden and the pie filling is cooked to piping hot, serve slices of pie with a side of steamed veggies or peas.

How long does a roast lamb take to cook? I cooked my leg of lamb for 3.5 hours but anything from 2.5 to 4.5 hours at 170°C. Cooking time will depend on the size of your leg of lamb so check as you are cooking until it is falling off the bone.

If you don't like chunky onions in you gravy: Either blitz the gravy with a stick mixer or you can pass it through a sieve to take out any chunky bits.

My family loves a traditional roast lamb and I'm sure yours will too. If you are looking for more delicious recipes you will love my Baked Garlic Chicken, Slow cooker moroccan lamb with apricots and Slow cooker lamb shanks.

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