Preheat oven to 475 levels. Mix breadcrumbs, Parmesan, and 1 tablespoon oil. In a gargantuan solid-iron skillet, raise meat sauce to a fleet simmer over excessive. Hotfoot in rice and grab some distance from warmth. High with onion, then fastidiously arrange zucchini in a single, quite overlapping layer. Season with salt and pepper, drizzle with smartly-behaved tablespoon oil, and prime with breadcrumb mixture. Return to warmth and raise to a simmer. Duvet with foil and bake 10 minutes. Accumulate foil and bake unless rice is cooked thru and breadcrumbs are golden, about 10 minutes more. Let frigid 5 minutes before serving.