In a large pot, heat a drizzle of olive oil over medium heat. Sauté the chopped onion and garlic until fragrant and translucent.
Add the carrots, potatoes, and zucchini to the pot. Stir and let cook for a couple of minutes.
Add the chopped tomatoes and stir to combine.
Pour in the water, add a pinch of salt, and bring the mixture to a boil.
Reduce the heat and let the stew simmer for about 20–25 minutes, or until the vegetables are tender.
Taste and adjust seasoning if needed. Serve hot, garnished with chopped fresh parsley and slices of warm bread on the side.