Preheat oven and toss squash slices with olive oil, salt, and pepper. Roast until tender and slightly caramelized. Roasting enhances natural sweetness and improves texture.
Heat olive oil in a pot and cook onions until soft. Add garlic, thyme, and chili flakes briefly to release aromas. This step builds the soup’s savory foundation.
Stir in drained beans and pour in broth. Let everything simmer gently so flavors blend. Beans soften slightly while keeping their shape.
Add roasted squash and chopped greens to the pot. Greens wilt quickly and squash absorbs broth flavor. Stir gently to keep squash pieces intact.
Stir in miso paste and lemon juice for balance. Taste and adjust salt and pepper as needed. These final touches brighten the entire dish.
Ladle into bowls and top with Parmesan and fresh herbs. Serve warm while broth is fragrant. Enjoy immediately for best texture.