11lb leg of lamb? Or is it mutton? How do I cook it??

Need help!
Just received a bone-in leg for our Easter tomorrow (received from a friend of a friend who distributes meat, so I can’t call the butcher back up) and its exactly 11 lbs.
All recipes I see are for 6-8 lbs - one chowhound thread suggests to the OP that their 12 lb leg must be mutton, not lamb.
What do you all think? Ever heard of an 11lb lamb leg?
Was planning on cooking a 6-7lb at 300 for 7 hours.
Not sure what to do with this giant piece though.. suggestions?
Looking specifically for time and temp help.
Many thanks!



Nancy April 19, 2020
Stephanie - congratulations on your gift!
But it sounds like a problem - so big, how to cook, how to use.
I would go for a traditional recipe with garlic and rosemary, if you like & have them around.
Or look through recipes for aromatics you like better.
And think of it like a big roast beef....I would roast all, use some for your Easter dinner, give some away packaged to guests, family or nearby friends, and store the rest in usable portions in the freezer.
Here are 3 recipes from UK, New Zealand and Ontario, where they both produce and eat lots of lamb. And a conversion chart for Celsius to Fahrenheit, as those areas use metric.
The Waitrose recipe (UK) recommends roasting at 180C for 25 minutes per 500g plus 25 minutes more to get medium doneness. That's at roughly 350F. 25 min for every 17 oz, plus 25 minutes, for medium.
That suggests about 10 hours (ugh! wow!)
If you have the time and and started your roast, use one of those guidelines.
If you don't have the time, and can perhaps partially carve or separate it halfway through, you will need less time.
Not sure about the name, but if you fear the leg is from an older animal, that's another reason to target medium done-ness (and not risk drying out a tougher cut of meat).
Good luck with this cooking adventure & happy Easter!
Nancy April 19, 2020
Correction on the time needed.
Should take about 5 hours, not 10.
My source said 25 minutes for each 500 grams and 25 minutes more total to cook to medium doneness.
11 lb is about 10 x 500 grams at 25 minutes each plus 25 for the whole roast.
So, 250 + 25 minutes = 315 min.
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