Preheat your oven to 350º and prepare a small casserole dish with cooking spray; I used a Pyrex pie pan. Slice the zucchini into thin rounds, in a mixing bowl toss the zucchini with olive oil and sprinkle with salt, set aside. In a separate bowl mix the Panko, thyme, pepper and parmesan cheese, set aside.
In a skillet over medium/low temp heat the canola oil and cook the onion until tender, about 5-7 minutes.
Add the garlic during the last minute and spread the mixture into the bottom of a casserole pan.
Place a layer of zucchini over the onion mixture and top with tomatoes, sprinkle the with the Panko mixture and continue layering; ending with a top layer of vegetables.
Sprinkle the Italian cheese over the top.
Bake for 40-45 minutes, until the cheese is golden and melted.
Remove carefully, cool 8-10 minutes and serve warm.
Coursesside dish, vegetable
Recipe by It Bakes Me Happy at https://itbakesmehappy.com/2013/02/vegetable-gratin-secret-recipe-club-reveal.html