Fill and boil your kettle, then fill a large pan with the hot water. Add a pinch of salt, cover and bring to the boil.

While the water comes to the boil, peel and thinly slice the red onion. Place a large frying pan on a medium-low heat and add 1 tbsp olive oil. Add the onion, season with salt and pepper and fry, stirring often, for 8-10 mins till the onion is glossy and lightly browned. If it browns too quickly or starts to catch, turn the heat down even more and add a few tbsp water to the pan.

The water should be boiling by now. Add the spaghetti and simmer for 8-10 mins till tender but still with a little bite. When it's ready, scoop a mugful of water out of the pan (mind your fingers, or use a ladle), then drain the spaghetti.

While the spaghetti simmers, trim the ends off the courgettes and use a vegetable peeler to peel them into ribbons. When you get down to the seeded cores thinly slice them. If you have a spiraliser, you can use it to ribbon the courgettes. Peel and grate or crush the garlic. Finely grate the zest from the lemon. Roughly chop the parsley.

Add the garlic, lemon zest and most of the parsley to the onion and cook, stirring, for 2 mins. Add the courgette ribbons and cook for 2 mins, stirring, till just starting to soften. Add the sheep's cheese to the pan with 2-3 tbsp of the pasta water. Stir to melt the cheese and make a smooth sauce.

Add the spaghetti to the frying pan and toss to mix. Add a few more tbsp pasta water if it seems too dry. Taste and add a pinch more salt or pepper if you think it needs it. Take the pan off the heat.

Squeeze the juice from half the lemon into a mixing bowl. Add 1 tbsp olive oil and a pinch of salt and pepper and whisk to make a dressing. Add the salad leaves and toss to dress. Serve the spaghetti in warm bowls, garnished with the remaining parsley, with the salad and wedges of the remaining lemon on the side.