1. Heat the olive oil in a large pot over medium heat.
2. Add the chopped onion and cook until translucent, about 5 minutes.
3. Stir in the minced garlic and cook for another minute.
4. Add the Arborio rice and cook, stirring frequently, until the edges are translucent, about 2-3 minutes.
5. Begin adding the chicken broth, one ladle at a time, stirring constantly and allowing the liquid to be absorbed before adding more.
6. After about 20 minutes, when the rice is almost cooked, stir in the pumpkin puree.
7. Continue to cook, adding more broth as needed, until the rice is tender and creamy.
8. Stir in the grated Parmesan cheese and season with salt and pepper to taste.
9. Serve hot and enjoy!