Roasted butternut squash with sweet spices, lime and green chilli

• 2 whole limes
• 4 tablespoons olive oil
• 1 medium butternut squash (about 900g)

Preheat the oven to 210°C/Gas Mark 7. Trim off the limes’ tops and tails using a small sharp knife. Stand each lime on a chopping board and cut down the sides of the fruit, following its natural curves, to remove the skin and white pith. Quarter the limes from top to bottom, and cut ea