Turn the pot to saute and add 2 tablespoons of butter. Add the sliced mushrooms and cook until mushrooms are soft, have released their liquid and the liquid has evaporated. 5-7 minutes.
Add the soy sauce and cook 1-2 minutes longer until the liquid is absorbed, then remove the mushrooms from the pot and set aside.
Add the remaining 2 tablespoons of butter, diced shallots and minced garlic. Cook for 3-4 minutes until the shallots are soft and fragrant.
Add the rice and cook for 2-3 minutes, just until you see the edges of the rice turn slightly translucent.
Add ½ cup of the broth and use a wooden spoon to scrape any bits from the bottom of the pot, then add the remaining broth, salt and thyme.
Stir to combine, then press cancel to turn off the saute function. With the valve of the lid open, place the lid on the pot and then turn the valve to seal.
Set the pot on high pressure for 6 minutes. When the timer is complete, turn the valve to quickly release the pressure. When the pin has dropped carefully remove the lid.
Give the rice a gentle stir, then add the shredded cheese and mushrooms.
Stir to combine until the cheese is melted. The risotto should be creamy and smooth. If it is too thick you can stir in a few tablespoons of broth until it reaches your desired consistency. It should be creamy, but not liquidy.
Serve garnished with additional parmesan cheese and fresh herbs, if desired.
Notes
This recipe can be made in either a 3qt or 6qt instant pot.Be sure to use freshly shredded parmesan cheese for the best results.If using table salt or fine sea salt, reduce to ¼ teaspoon.Time to reach pressure is an estimate and varies by pot. It can depend on the size or model.