Preheat the oven to 180°C (355°F). Place the rice and stock in a 22 x 30cm (8½ x 12 in) 10-cup (80 fl oz) capacity baking dish and stir to combine. Cover tightly with foil and cook for 40 minutes or until most of the stock is absorbed and the rice is al dente. Add the parmesan, butter, salt, pepper, spinach, fetta and pine nuts and stir until the butter is melted. Serve immediately. Serves 4.