Preheat the oven to 425°F (220°C) and line a baking sheet with parchment paper.
In a shallow bowl, combine the breadcrumbs, garlic powder, onion powder, salt, and black pepper. Mix well.
In another bowl, whisk the egg and olive oil together until well combined.
Dip each squash round into the egg mixture, allowing any excess to drip off, then coat it in the breadcrumb mixture, pressing gently to adhere.
Place the coated squash rounds in a single layer on the prepared baking sheet.
Sprinkle the shredded mozzarella and grated Parmesan evenly over the squash rounds.
Bake in the preheated oven for 20-25 minutes, or until the cheese is bubbly and the squash is tender.
For extra crispiness, broil for an additional 2-3 minutes, watching closely to prevent burning.
Remove from the oven and let cool for a few minutes before serving. Garnish with fresh parsley if desired.