Zucchini gratin is a great way to eat your garden harvest. Served alongside a salad it is the perfect way to enjoy summer.
Sauté the onion over low heat until soft, but not colored. Slice the zucchini coin thin and then add to the onions and sauté an additional 2-3 minutes.
Set aside. In a large bowl, pour 1 cup of the milk over the bread crumbs; add a splash of olive oil, eggs, thyme, 1/2 cup cheese, salt and pepper.
Stir until combined. Add the onion zucchini mixture and rice. Pour into prepared gratin dish. Smooth the surface and pour the remaining 1 cup of milk over the top. Sprinkle with remaining cheese. Bake, uncovered, for one hour or until golden on top.