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. If you enjoy roast meals, be sure to check out my Roast Pork with Gravy.
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.
Step by step instructions:
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.
Recipe FAQs:
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.
Either blitz the gravy with a stick mixer or you can pass it through a sieve to take out any chunky bits.
Storage:
Store any leftover Roast Lamb with Onion Gravy in an airtight container in the fridge for up to three days. Reheat in the microwave until piping hot.
Top tips:
- If you don't like chunky onions in your gravy you can use a stick blender to blend it until smooth.
- I served potatoes, kumara and butternut pumpkin with my roast lamb. Parsnip, carrots and brussel sprouts would also be delicious.
- 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.
Related Recipes:
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Roast Lamb with Onion Gravy
This traditional roast lamb is served with a delicious homemade onion gravy.
Ingredients
- 2 onions
- 2.5kg lamb leg
- 1 Tbsp olive oil
- ½ tsp sea salt
- 1 Tbsp rosemary, chopped
Gravy
- 1 beef oxo cube
- ½ cup boiling water
- 2 Tbsp cornflour
- 2 Tbsp water
Instructions
- Preheat oven to 170.C fan bake.
- Cut onions into wedges and add them to the base of a oven-proof casserole or cast iron dish.
- Pour in 2 cups (500ml) of water and place 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.
- Peel and chop your chosen veggies, coat in olive oil and bake on a tray until golden and cooked through. 1-1.5 hours before serving.
- After 3-3.5 hours the lamb will be tender and the fat crispy. Remove it from the dish and cover in tinfoil to rest until serving.
- Add the dish to the hob on the stovetop and bring to a simmer. Mix oxo cube with boiling water and pour into the dish.
- Combine cornflour with 2 tablespoons of water then pour into then gravy. Simmer stirring until the gravy thickens up. Use a ladle to pour it into a gravy boat.
- Carve hot lamb and serve with onion gravy, roasted veggies, peas and mint sauce or jelly.
Notes
- If you don't like chunky onions in your gravy you can use a stick blender to blend it until smooth.
- I served potatoes, kumara and butternut pumpkin with my roast lamb. Parsnip, carrots and brussel sprouts would also be delicious.
Nutrition Information:
Yield: 8 Serving Size: 1Amount Per Serving: Calories: 860Total Fat: 55gSaturated Fat: 23gTrans Fat: 0gUnsaturated Fat: 28gCholesterol: 300mgSodium: 359mgCarbohydrates: 3gFiber: 1gSugar: 1gProtein: 83g
Nutritional values are approximate. Please use your own calculations if you require a special diet.
Thank you for checking out this recipe. I hope you enjoy making and eating it! If you have any questions, queries or feedback, please feel free to leave a comment below.
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Vanya
Elizabeth Marie says
Looks delicious! Do you cover the dish with a lid while cooking the meat?
VJ cooks says
I don't cover it. This helps the skin to render and become nice and crispy.
Mel says
I have just put mine on now for dinner tonight..
Gene says
Cooking one right now for the family. The only thing I've done different is I've boiled my roast veges for 10min and aired them out prior to roasting them (something I learnt from my Nana). Smells beautiful
VJ cooks says
What a great tip! Hope you enjoyed your meal 🙂
Gene says
I've told a few people today that it is the best roast I've ever had in my life. I've never had the Lamb taste so good. Thank you so much for all of your tips and recipes! I've been going 2 weeks straight cooking/baking a range of your recipes and they all taste so good! Will recommend your recipes all the time 🙂
VJ cooks says
Oh Gene! That makes me so happy to hear! Thank you for taking the time to write to me. I'm so happy you're enjoying my recipes 🙂
liz says
with countdown having the legs of lamb on special - i bought one today - for the first time in years - a much more affordable price - if i had the room i would have bought 2 - thanks for the recipe - i will be trying this for New Year Merry Christmas and i hope its a peaceful time for you and your family so roll on Christmas day
and on a side note i will be trying out the ambrosia for Christmas - checked in with the Dr and as long as i dont have a huge bowl of it - just enough to satisfy the taste buds i will be fine - apparently -so roll on Christmas Day
VJ cooks says
Thanks Liz, I hope you had a wonderful holiday season.
Aims says
Can I use the slow cooker to do this?
If so how many hours should I cook it for and should it be on high or low? 🙂
VJ cooks says
Oh I've never tried this is a slow cooker before sorry!
Candra Van Haeren says
What potato's do you recommend are best for roasting?
VJ cooks says
I like using agria potatoes, or bags that are labelled as 'roasting' potatoes.
Jan D says
Thank you for an easy delicious roast lamb recipe. I served mine with roast pumpkin and kumara, steamed broccoli and peas and carrots. Topped off with your yummy gravy and must have mint sauce. Will definitely be making again.
VJ cooks says
Oh wow, that sounds sensational. Thanks for sharing, Jan.
Tamsin says
This is the best roast lamb I’ve ever had. My husband bought two legs of lamb when they were on special at Countdown. I used this recipe for the second one after being disappointed with my own version for the first leg and everyone loved it. The gravy was delicious too so I’m going to make the pie tomorrow night.
VJ cooks says
Thank you so much for the feedback, Tamsin. I'm super happy to hear you had a great result in the end 🙂 I saw those legs of lamb on special over Easter - that was a crazy good deal!