Sauté Aromatics
Heat olive oil in a large pot over medium heat.
Add onion and cook until soft, about 4 minutes.
Stir in garlic and cook for 1 minute until fragrant.
Add Broccoli and Beans
Add chopped broccoli (florets and stems), cannellini beans, thyme, salt, pepper, and red pepper flakes (if using).
Pour in the vegetable broth and bring to a boil.
Simmer
Reduce heat, cover, and simmer for 12–15 minutes until broccoli is very tender.
Blend the Soup
Use an immersion blender to puree the soup directly in the pot until smooth and creamy.
Alternatively, carefully transfer the soup in batches to a blender and blend until smooth. Return to the pot.
Finish and Serve
Stir in lemon juice and nutritional yeast or Parmesan, if using. Adjust seasoning to taste.
Ladle into bowls and garnish with fresh parsley or chives.