Select Sauté and set to Less, then add the 1 tbsp oil to the inner pot.
Stir in the chopped onion and garlic. Cover with glass lid and sweat for 5-6 minutes.
Add the mushrooms and stir, then leave for another 2 minutes covered with the glass lid.
Stir in the rice and wait for it to go translucent.
Add a little bit of stock and use a wooden spoon to remove any caramelised or burnt-on bits at the bottom of the inner pot.
Then stir in the remaining vegetable stock.
Put on the lid, and select Manual High Pressure and programme the time for 5 minutes followed by quick pressure release.
Remove the lid and stir in nutritional yeast flakes and the spinach until it wilts.