Let’s get cooking! These steps are straightforward enough to tackle even on the busiest of weeknights.

1. In a large pot, heat the olive oil over medium heat. Add the chopped onion, garlic, carrots, and celery. Sauté until the onions are translucent and the veggies are tender, about 5 minutes.
2. Stir in the dried thyme, rosemary, and red pepper flakes, letting them bloom in the heat for about 1 minute.
3. Add the vegetable broth, cannellini beans, and diced tomatoes. Bring the mixture to a gentle boil, then reduce the heat to low and let it simmer for 20 minutes, allowing the flavors to meld.
4. Using an immersion blender, blend the soup slightly to thicken it, leaving some beans whole for texture. If you don’t have an immersion blender, you can transfer a portion of the soup to a regular blender and then return it to the pot.
5. Stir in the heavy cream and fresh spinach. Cook for an additional 5 minutes until the spinach has wilted and the soup is heated through.
6. Season with salt and pepper to taste. Serve hot, garnished with fresh basil if desired.