Preheat the oven to 400°F
Pat the Cornish hen dry
Rub the hen with olive oil or melted butter
Season with salt, black pepper, garlic powder, and herbs
Place the hen in a roasting pan or on a baking sheet
Roast for 45 to 60 minutes
Baste once or twice during cooking if desired
Cook until the thickest part reaches 165°F
Remove from the oven
Let rest for 10 minutes
Carve and serve