Peel your butternut squash. Cut in half and scoop out the seeds. Chop the flesh into 2 cm chunks.
Peel and chop the onion into thick slices. Halve the peppers and scoop out the seeds and white pith. Chop the peppers into bite-sized pieces. Peel and thinly slice the garlic. Roughly chop the tomatoes.
Heat 1 tbsp oil in a large, heavy-based pan. Tip in the squash and cook for 5-6 mins till it starts to brown. Season. Transfer the squash to a bowl.
Add ½ tsp oil to the pan. Fry the onion and peppers for 3-4 mins till just softened. Add the garlic and fry for 1 min. Add the squash back to the pan.
Pour in 2 tbsp of the red wine vinegar. Bubble for 1 min, then tip in the tomatoes and stir well. Add the raisins and the olives. Season to taste.
Cover and cook for 30 mins till the squash is soft and the sauce thick. Stir now and then.
While the caponata is cooking, cook the quinoa. Rinse the quinoa for 1-2 mins under cold water. Tip into a pan. Add a pinch of salt. Pour in 300ml boiling water. Cover. Simmer over a low-medium heat for 20 mins or till the water is absorbed.
Roughly chop the chervil leaves. Stir the cooked quinoa through the caponata. Scatter over the chervil and serve in warm bowls.