Heat oven to 190C/fan 170C/gas 5. Cut squash in half lengthways, then scoop out seeds and membranes. Brush insides with a little oil and place in a roasting tin filled to 1cm with water. Roast for 20-30 mins until almost tender when tested with a sharp knife. Scoop out some of the flesh and roughly chop.
Meanwhile, heat remaining oil in a pan, then cook onion and garlic for 5 mins until the onion is tender. Stir in the rice and fry for 1 min. Add the vegetable stock and cook for a further 10-12 mins until the rice is tender and the liquid has all been absorbed.
Stir in chopped squash flesh, sun-dried tomatoes, goat's cheese, half the sage leaves and seasoning.
Stuff the squash with the filling, top with remaining sage leaves and cover with foil.
Return to the oven and cook for a further 15 mins until the cheese is melted and all is heated through. Stand for 5 mins before serving with a green salad.
Recipe from Good Food Vegetarian Christmas magazine, December 2006