Pour in the vegetable stock, milk, water, and pumpkin puree. Whisk to incorporate everything and turn heat down to medium and let mixture thicken up, about 7-10 minutes.
3 cups vegetable stock, 1/2 cup whole milk, 1/2 cup water, 3/4 cup pumpkin puree
Add the orzo to the pot and stir to incorporate. Cover pot and let orzo cook for 12 minutes, or however long the instructions on the box says.
16 ounce orzo pasta
Once the orzo is done, stir in the parmesan cheese, sage, cayenne pepper, salt, and pepper. Stir altogether with a wooden spoon to combine and then cut the heat.
1 1/2 cups freshly grated parmesan cheese, 1 tablespoon fresh sage, 1/2 teaspoon cayenne pepper, Salt and pepper
Serve warm with additional parmesan cheese on top.
Notes
If your mixture seems too thick, you can add more vegetable stock or water to thin it out prior to adding the pasta.