Heat olive oil in a skillet over medium heat. Add the onion and garlic, and sauté until softened. Stir in the hearts of palm rice, pumpkin puree, vegetable broth, and sage. Bring to a simmer.
Reduce heat and simmer until the liquid has been absorbed and the rice is cooked through.
Stir in the Parmesan cheese and parsley until melted and combined.