Heat olive oil in a large pot over medium heat.
Add the diced onion and sauté until translucent, about 5 minutes.
Stir in minced garlic and sauté for another minute until fragrant.
Add the diced bell pepper and sauté for another 5 minutes.
Add zucchinis and eggplant, cooking for about 7-10 minutes until they start to soften.
Pour in the canned tomatoes and vegetable broth; stir to combine.
Season with thyme, salt, and pepper; bring to a gentle boil.
Reduce heat, cover, and let simmer for 20-30 minutes to allow the flavors to meld.
Taste and adjust seasoning if necessary before serving.