Black meat at 150c?

[BML]

I attempted to cook a roast lamb with a Sherry/tomato gravy and having done it before I thought, "no problem". Made some slits in the leg of lamb, stuffed them with mixed herbs, a cup of sherry and half a cup of water under the trivet with a mix of tomato sauce and Worcester sauce for covering it and later to baste it.
Started for 20 minutes at 200c dropping it to 150c and two hours only to find that the dish had boiled dry and was burnt as was the leg of lamb. I’m assuming that there is a fault with the oven temperature control and if I’m correct is there a way to test it such as a special thermometer or have I made an awful mistake?

 

[dragnlaw]

Oven thermometers are cheap and usually easy to find. Under 10$ Cdn. and also under 10L from what I googled. Place on rack in oven and just look at it once in a while. Will give you a good idea of what is going on.

My quick/first thoughts on your problem:-

As to the lamb. I think your temperature choices were fine. Although I personally would have checked the meat with a meat thermometer (different than the oven thermometer) after about an hour or an hour and a half.

Your sherry and tomato, again, to my mind, are both easily dried. I think I might have saved the sherry to make a sauce/gravy at the end. I'm not sure how I would have handled the tomato sauce. Other than for meatloaf and liquidly pasta dishes I can't remember using a tomato sauce in a recipe for basting. but that's my memories on first thoughts

Wait for some other answers - sure to be better than mine.
AND I'm so sorry it was ruined! Here lamb is not exactly cheap and I would have been horribly upset had I lost my meal!

 

[BML]

Many thanks for your most helpful reply to my thread. I've ordered an oven thermometer and if as I suspect the temperature controller is dead I will see if its worth replacing it otherwise, a new oven.