Melt the butter in a frying pan, sauté the onion, add the rice and sauté until translucent. Add the saffron. Dissolve the bouillon in the water and add little by little to the rice, stirring well, ensuring that the rice is covered with a small amount of liquid at all times. After 10 mins. add the squash, then cook for a further 10 mins. until the rice is creamy and al dente. Mix the double cream cheese and half of the Parmesan into the risotto, season and plate up. Garnish with the remaining Parmesan and the pumpkin seeds.