- Preheat your oven to 425°F. 
- In a large bowl, combine the green beans, olive oil, garlic powder, onion powder, salt, and black pepper. Toss until the green beans are evenly coated. 
- Spread the green beans in a single layer on a baking sheet. 
- Roast in the preheated oven for 15 minutes. 
- Remove the baking sheet from the oven and sprinkle the grated Parmesan cheese over the green beans. 
- Return to the oven and roast for an additional 5-7 minutes, or until the cheese is melted and the green beans are tender and slightly crispy. 
- Serve warm.