Method
Preheat oven to 200°C (Gas Mark 6). Carefully cut the squash in half lengthways, then scoop the seeds out and discard. Put the squash on to a baking tray and drizzle over the olive oil – rub the oil all over the squash halves, especially the cut edges. Sprinkle over the cumin seeds, a good pinch of sea salt and some black pepper, then turn the squash cut-side down and put the tray into the hot oven. Cook until the squash is tender when pierced with a sharp knife (about 45 minutes), then leave to cool for a few minutes. Leave the oven on. While the squash is cooking, put the drained lentils into a large mixing bowl and crumble in the cheese, then add the yoghurt, chilli flakes (if using), spinach and parsley, reserving a few parsley leaves to garnish. Mix well and season to taste. When the squash has cooked and cooled a little, carefully turn each half over and use a spoon to scoop out some of the flesh to leave a hollow – but be sure to leave enough to form a ‘container’ strong enough to hold the lentil mixture. Mash the scooped-out flesh into the lentil mix, check you’re still happy with the seasoning, then spoon the mixture into the butternut halves, dividing it equally between the two. Grate over the lemon zest, then return the tray to the oven and roast for 10-15 minutes more, or until the filling is golden. Serve straight away, with the reserved parsley leaves scattered over.