This provencal vegetable soup, called “soupe au pistou” in French, is a well-known speciality of Provence. It contains a variety of vegetables, and most importantly comes with pistou, which is the French version of pesto. Pistou is a basil-garlic paste, which differs from pesto in that it does not contain any nuts. The basil paste is traditionally added to the soup just before serving, sometimes immediately mixed with the rest of the soup, or other times, placed in the middle of the soup so everyone can choose as little or as much as they wish. I like it best when the pistou is mixed with the soup at least 15 minutes before serving, so as to allow time for the flavors to mingle. I find it even better on the second day, when the vegetables and pistou have mingled overnight. Pistou is really the highlight of this soup and what makes it so delicious!
The traditional version of this provencal soup adds bacon to the vegetables, but I make mine with vegetables only, as I like it as light and healthy as possible. The soup usually tastes best on the second day, so it is a good idea to make more than you actually need right away.
Peel all vegetables (except for the zucchini). Slice the carrots and dice all other vegetables.
Fill a big pot with water. Season with salt and pepper. Bring to a boil. Add the vegetables, cover, and cook on low heat for 1 hour.
In the meantime, prepare the pistou. Grind the basil to a paste in the mortar (or blender). Add the tomato (peeled, seeds removed, and diced), and the minced garlic, mix, and grind again. Add the olive oil, one drizzle at a time, until you get the consistency of a paste. Taste and season with salt if needed.
Take the soup out of the pot and pour it into a serving dish. Season with salt and pepper, and add the pistou. Personally, I like to mix the pistou with the rest of the soup 15 minutes before serving, and I find it most delicious on the second day, when the vegetables have mingled with the pistou overnight. Enjoy!