Heat your oven to 190°C/Fan 170°C/Gas 5. Halve the courgettes lengthways. Use a teaspoon to scoop out the seeds. Pop the courgettes on a baking tray. Bake for 20 mins to soften slightly.
While the courgettes bake, tip the quinoa into a sieve. Rinse it under cold water for 1-2 mins. Tip the rinsed quinoa into a small pan. Add 150ml boiling water and a pinch of salt. Cover. Bring to the boil. Turn the heat right down and gently simmer for 12-15 mins till the water is absorbed.
While the quinoa cooks, tip the cashews into a dry frying pan. Toast for 2-3 mins, shaking the pan occasionally, till they’re browned. Tip out onto a chopping board. Roughly chop them, then scoop the chopped nuts into a bowl.
Peel and finely slice the shallots and add to the cashews. Peel and finely chop the garlic. Add that to the bowl. Finely grate in the lemon zest. Tear in the basil leaves. Finely chop the mint leaves and add them too.
Add half the quinoa to the cashew bowl once it has cooked, draining off any excess water (keep the rest of the quinoa for later). Season well with salt and pepper and squeeze in a little juice from the zested lemon. Stir together.
Take the courgettes out of the oven. Spoon in the quinoa stuffing. If there’s any extra, keep it in the bowl for later. Return the courgettes to the oven and bake for 20 mins till tender.
While the stuffed courgettes bake, roughly chop the tomatoes. Tumble them into a bowl with the lamb’s lettuce and the cooked quinoa you reserved in step 5.
Whisk 1 tbsp balsamic vinegar with 1 tbsp olive oil, a squeeze of lemon juice and some salt and pepper. Toss with the salad. Serve the stuffed courgettes with the salad and any remaining stuffing on the side.