Peel the squash, cut it into 1-inch chunks and place the chunks in an ovenproof dish. Drizzle with a little olive oil, then add the chilli flakes and cumin seeds (whole spices are better than powdered spices as they tend to clump together in the oil). You could also use a whole fresh chilli in place of the chilli flakes. Roast the squash for 25-30 minutes until almost tender.