Heat the olive oil in a large skillet or frying pan over medium heat.
Add the sliced onion and minced garlic to the pan. Sauté for about 2 minutes, or until the onion becomes translucent.
Add the diced eggplant to the pan and cook for about 5 minutes, stirring occasionally, until it starts to soften.
Next, add the diced zucchinis, red bell pepper, yellow bell pepper, and green bell pepper to the pan. Cook for an additional 5-7 minutes, or until the vegetables are tender.
Stir in the diced tomatoes, dried thyme, dried oregano, salt, and black pepper. Continue to cook for another 5 minutes, allowing the flavors to meld together. If the mixture appears too dry, you can add a splash of water.
Taste and adjust the seasoning if needed.
Remove the ratatouille from the heat and garnish with fresh basil leaves and grated Parmesan cheese (if desired).
Serve hot as a side dish, over pasta, or with crusty bread.Enjoy your homemade Ratatouille!