Heat the oven to 200 degrees. Peel and cut the pumpkin into thin slices, do the same with the potatoes and onion. Mix with pumpkin, potato and onion in an ovenproof form.
Mix vegetable cream, salt, pepper and pressed garlic in a bowl. Pour mixture over pumpkin and potatoes and grate in oven 200 ° for 30 minutes.
Remove the gratin and sprinkle over the vegan parmesan and bake for another 10 minutes. Serve with vegetable steaks or vego buns