Preheat oven to 400 degrees Fahrenheit. Toss cauliflower florets with olive oil, salt, and pepper on a large baking sheet. Roast for 30 minutes, until soft and caramelized around the edges.

Meanwhile, heat one tablespoon of olive oil in a heavy pot over low heat. Sauté onions and garlic until soft and translucent, about 20 minutes. Add bay leaves, thyme, vegetable stock, and roasted cauliflower.

Bring to a boil, then reduce heat and simmer for 15-20 minutes, until the cauliflower is soft and can be pierced with a fork.

Remove bay leaf and thyme. Transfer to a blender and blend for 15 minutes, gradually drizzling in another two to three tablespoons olive oil, until consistency is creamy and velvety.

Heat olive oil in a shallow skillet, then add mushrooms. Sprinkle with salt and fresh thyme, then sauté until slightly golden and caramelized.

In a small pot, heat olive oil on lowest flame with basil for approximately five to 10 minutes. Let it sit and cool, about one hour. Strain and set aside.

Ladle soup into a shallow bowl. Top generously with mushrooms, microgreens, and chopped pistachios. Drizzle with herbed oil and use a skewer to create swirls around the soup.