Add one tablespoon of butter into a deep pot and place over medium heat. Add the arborio rice and cook for two minutes, until lightly toasted. Add the white wine and simmer together until mostly absorbed.
Add one cup of the vegetable broth and cook until absorbed. Add the remaining broth and stir until al dente.
While the risotto is cooking, add butter to a non-stick pan and place over medium heat. Add the onion and garlic and cook until fragrant. Add the mushrooms and cook for 4-5 minutes, until they have softened. Add the thyme and season with salt and pepper.
Once all the broth is absorbed from the arborio rice, add the mushroom mixture and mix well. Stir through the parmesan cheese and serve immediately.
Notes
TO STORE: Leftovers can be stored in the refrigerator for up to 5 days in an air-sealed container.TO FREEZE: Put the leftovers in freezer-safe containers and freeze them for up to 6 months.TO REHEAT: You can reheat mushroom risotto in the microwave or pan.