If using a regular blender to puree the soup, wait for it to cool at least 5 minutes before blending. Do not fill the blender more than halfway (work in batches); to avoid splattering, remove the cap from the hole in the blender lid and cover it with a dish towel while blending.
Don’t have herbes de Provence on hand? Use dried thyme leaves instead.
Want to reduce calories even more or make this a vegan soup? Substitute vegetable broth, use butter instead of olive oil for cooking the veggies, and top servings with whole wheat croutons rather than bacon.