Prepare all ingredients.

Crush and mince the garlic, and coarsely chop the onion. Sauté them in a pan with olive oil over high heat until the onion turns translucent, then reduce to low heat.

When the onion turns brown, add the canned tomatoes, bay leaf, dried basil, and season with salt and pepper. Simmer for 5 minutes on low heat.

While the sauce simmers, thinly slice the zucchini, eggplant, and tomato.

Season the sliced vegetables with salt and pepper.

Once the sauce is reduced, chop fresh basil and stir it into the sauce.

Pour half of the tomato sauce into an oven-safe dish.