Heat the olive oil over medium heat in a Dutch oven and add the onion and celery. Cook, stirring, until tender, about 5 to 8 minutes. Do not allow these ingredients to brown. Add a generous pinch of salt. Add the garlic and cook, stirring, until the garlic smells fragrant, 30 seconds to 1 minute.

Make bouquet garnie

Add the broccoli, potatoes or rice, water or stock, bouquet garni, and salt, and bring to a boil. Reduce the heat, cover and simmer 30 minutes. Remove the bouquet garni. Using a hand blender purée the soup.

Stir in the spinach and let sit for a minute off the heat. Using a hand blender purée again the soup. Add freshly ground pepper, taste and adjust salt. Return to the pot and heat through, stirring. Adjust seasoning to taste with salt and pepper.