Pre-heat your oven to 425 degrees. Line a baking sheet with foil or parchment.
Arrange the cauliflower florets on the baking sheet. Drizzle with olive oil and season generously with kosher salt and fresh ground pepper. Toss to coat.
Roast your cauliflower for 25 minutes, stirring once halfway through the cooking time, until tender and browned.
Heat the remaining tablespoon of olive oil in a Dutch oven or heavy-bottomed pot over medium heat. When hot, add the onions and garlic and cook for about 4 minutes until the onions become translucent and the garlic is fragrant. Add the wine and cook for about 2 minutes, stirring regularly, until most of the liquid has evaporated.
Add the roasted cauliflower to the Dutch over, along with the bay leaf and vegetable stock. Bring to a boil, then lower to a simmer and cook for 20 minutes.
Puree your soup with an immersion blender (or in a regular blender/food processor) until it’s silky smooth. Stir in the grated Parmesan. Season with extra salt and pepper to taste.
Ladle the warm soup into bowls and garnish with a drizzle of olive oil (if you like), toasted almonds, raisins, parsley and red pepper flakes. Go ahead and grate some more Parmesan on top if you’re feeling crazy.