Arrange a rack in the middle of the oven and heat to 450 degrees. Line a rimmed baking sheet with parchment paper.

Place the gnocchi, peppers, tomatoes, onion, salt and black pepper in a large bowl. Drizzle with the oil and gently toss to combine. Spread gnocchi mixture out evenly on the prepared baking sheet.

Roast, stirring halfway though, until the gnocchi are plump and the vegetables are tender and carmelized, 18 to 20 minutes total.

To serve, spoon the gnocchi and vegetable mixture into individual bowls and garnish with Parmesan cheese.