Heat the olive oil in a large pot over medium heat.
Add the diced onion and sauté for 5-7 minutes until translucent.
Stir in the minced garlic and cook for an additional 1-2 minutes.
Incorporate the diced zucchini, eggplant, and bell pepper, cooking for 5-7 minutes.
Add chopped tomatoes and cook for another 5 minutes, stirring often.
Pour in the vegetable broth, thyme, basil, and season with salt and pepper.
Bring the mixture to a boil, then reduce the heat and simmer for 20-25 minutes.
Taste and adjust seasoning if needed before serving hot.