Preheat oven to 400F. Place cashews in a bowl of water and let soak. While cashews are soaking, put cauliflower, garlic and carrots in a large bowl. Drizzle bowl of vegetables with olive oil and sprinkle with salt and pepper. Mix until evenly coated then spread evenly on a sheet pan. Place onion and peppers in the bowl used for vegetables then drizzle with olive oil and sprinkle with salt and pepper. Mix until evenly coated then spread evenly on a second sheet pan. Place both sheet pans in the oven and roast vegetables 20-30 minutes or until they are tender and edges start to brown. Note that the onion and peppers are likely to be done earlier than the other vegetables.
Drain and rinse cashews then place them in a high-powered blender. Peel roasted garlic cloves add them to the blender along with all of the vegetables. Add miso, cumin, sriracha and vegetable broth to blender. Blend on high until smooth and creamy. Garnish with croutons and parsley.