Heat the oil in a large frying pan and add the squash in a single layer. Season well with salt and pepper and cook over a medium heat for about 10 minutes until lightly browned.
Meanwhile, melt the butter in a flameproof casserole dish, add the onion and garlic and cook for 2–3 minutes until softened. Stir in the pine nuts and quinoa and cook for 1 minute or until the quinoa is starting to pop. Add the wine and cook until it has been absorbed.
Stir in the squash, cinnamon stick and stock. Bring to the boil, season to taste with salt and pepper and stir well.
Cover the dish with the lid and cook in a preheated oven, 190°C (375°F), Gas Mark 5, for 25 minutes until the quinoa is just tender.
Stir in the mint, then scatter over the feta and pomegranate seeds. Serve immediately.