01 - Preheat your oven to 425°F. Line a baking sheet with parchment paper.
02 - Arrange the cabbage wedges, onion, carrots, and garlic cloves on the baking sheet. Drizzle with 2 tbsp olive oil and sprinkle with half the salt, black pepper, thyme, and smoked paprika. Toss to coat evenly.
03 - Roast vegetables for 25-30 minutes, turning halfway through, until cabbage edges are golden and caramelized.
04 - In a large soup pot, heat the remaining 1 tbsp olive oil over medium heat. Add the roasted vegetables and drained beans. Stir to combine.
05 - Pour in vegetable broth. Bring to a boil, then reduce heat and simmer uncovered for 10 minutes.
06 - Use an immersion blender to blend the soup until creamy but still slightly chunky. Alternatively, blend in batches in a blender, then return to pot.
07 - Stir in the heavy cream and adjust seasoning with additional salt and pepper if needed. Heat gently for 2-3 minutes.
08 - Ladle into bowls and garnish with fresh parsley and red pepper flakes, if desired. Serve hot.