Spiralized Onions with Crispy Parmesan Breadcrumbs

Position racks in upper and lower thirds of oven; preheat to 425 degrees F. Coat 2 large rimmed baking sheets with cooking spray.

Using a vegetable spiralizer, cut onions into long thin strands. Place in a large bowl and toss with oil.

Pulse bread in a food processor into crumbs. Add to the onions along with Parmesan, pepper, 1/4 teaspoon salt and cayenne; toss to coat. Divide between the prepared pans.

Bake, stirring once halfway through and rotating the pans from top to bottom and back to front, until browned in spots, 25 to 30 minutes. Sprinkle with the remaining 1/4 teaspoon salt and serve hot.