Preheat the Instant Pot by selecting the Sauté setting. Heat the oil in the preheated pot for a few seconds, then add the onion, garlic, and ¼ teaspoon of the salt. Cook until golden, 2 to 3 minutes, stirring occasionally. Add the mushrooms, wine,nutritional yeast, soy sauce, oregano, thyme, and pepper and cook for 1 minute longer. Add ¼ cup (60 ml) of the stock, then place the cauliflower and cashews in a steamer over the mushrooms. Select the Cancel setting.

Lock the lid into place, set the Pressure Release Knob to Sealing, select the Pressure Cook/Manual setting at high pressure, and set the cook time to 10 minutes. Once the cooking cycle is done, let the pressure release naturally. Open the lid and use silicone mini mitts to remove the steamer. Carefully transfer the cauliflower and cashews to a blender with about one-third of the mushrooms. Add 2 ¾ cups (650 ml) of stock and the remaining ½ teaspoon of salt to the blender and blend until smooth.

Pour the cauliflower puree into the pot and select the Sauté setting. Stir well to mix and taste for seasoning, adjusting if needed. If it is too thick, add ½ to 1 cup (120 to 240 ml) more stock. When the soup has come to a boil, select the Cancel setting.

Serve the soup hot, topped with the garnishes and with vegan garlic bread.