Preheat the oven to 350 degrees.  Spray a large oval baking dish with cooking spray.  Set aside.

Use a mandolin or food processor with the slicing attachment to slice the tomatoes, zucchini, potatoes, and eggplant as thinly as possible – about ⅛-inch thick.

Bring a large pot of water to a full rolling boil and add the sliced potatoes.  Allow them to cook for about 3 or 4 minutes. Drain and rinse with cold water to stop the cooking process.

Lightly toss all of the vegetable slices with salt, pepper, and 2 tablespoons olive oil.  Set aside.

In a skillet over medium heat, add the remaining 1 tablespoon olive oil, onions, and garlic.  Saute the vegetables until soft and translucent, about 10 minutes.  

Pour in the canned tomatoes, red peppers, carrot, Italian seasoning, thyme, rosemary, and bay leaf.  Stir to combine and simmer for about 10-15 minutes or until most of the liquid has evaporated. 

Remove from the heat and discard the bay leaf.

Spoon the sauce into the bottom of the prepared baking dish.

Using the thinly sliced vegetables, arrange the slices in an alternating pattern along the outer edge of the dish.  Follow the outer edge of the dish and work in a circle towards the middle until the dish is full.

Cover the baking dish with foil and bake in the preheated oven for 40 -45 minutes.  Remove the foil and continue to bake for another 10 minutes.

Serve garnished with parsley or a sprinkle of fresh rosemary.

This dish can be served either hot or cold.