Roast squash for 25 mins with olive oil salt and pepper at 400 deg F
Soften finely chopped onion, begin at high heat, add a pinch of salt, cover and cook for 10 mins until sloppy and lightly colored. Crush garlic and add, add oregano, passata and chilli flakes. Simmer till thick then stir in lentils and olives, fold in squash. Transfer to a 3 liter gratin dish. Blanch the spinach for 1 min, drain and squueze dry. Peel chunk rinse and boil the potatoes. Drain and mash in butter and milk. Tuck balls of spinach in the lentils, add chunks of feta. Spoon the mash over the top. Add grated nutmeg, scraps of butter and parmesan.
Bake at 400 deg F for 20 mins until crispy.