The solution was easy. Take some leftover roast lamb, leftover mint sauce (or a good tsp of fresh or dried, about 2cm of grated cucumber, and mix it all together with some leftover couscous (if you don't have leftover couscous it cooks really quickly, or rice, or pasta), and sprinkle with a little flaked chilli.
Lovely. Can't wait until the next roast.
For my thrifty use of mint sauce, homemade of course, I am entering it into Lavender & Lovage's and London Busy Body's Herbs on Saturday challenge.