Preheat the oven to 375 degrees.
Dice the onion and place it in the bottom of the dish along with the minced garlic.
Coat with EVOO
Pour in a small can of tomato sauce (paste will also work)
Thinly slice all the rest of the veggies
Place the sliced veggies in the baking dish vertically, alternating the same pattern over and over again
Drizzle EVOO over the top of the veggies
Sprinkle with salt and pepper and thyme
Cover the dish and bake it for about 30 minutes then remove the foil and top it with cheese. Bake for another 15 to 20 minutes until the potatoes and veggies are soft.