While this was delicious in part, good flavours and the herb crumb option being quite acceptable, the recipe used was simply wrong, which is a crime worthy of purgatory on these pages.
No, it is not possible to cook a lamb joint on 140c in 15 to 20 minutes. For sure I found my eyebrows reaching for loftier heights in their attempt to warn me of the folly this instruction had in store. But my blind faith won out and 25 minutes later, with 5 for the resting, I found myself cutting into a mostly raw lamb joint.
I pumped the oven to 190c and added 15 minutes, much more satisfactory. Leading me to think 25 to 30 minutes at 190c is the way to go. Although I will say the middle of the joint was probably still a little rare for most. But was delicious nonetheless.
The houmous with olive oil was a wonderful accompaniment to the lamb working as a flavoursome sauce. The broccoli was rotated along with the lamb and worked well.
This all had the sight sting in the tail that I belive the joint was actually turning bad, as both of us had a sensitive stomach in the evening. Oh well. You can't win then all, and this makes more eager to try again soon.
From https://www.houseandgarden.co.uk/recipe/roasted-rack-of-lamb... And there may it rest for all eternity.