Preheat the oven to 400°F. Line a baking sheet with parchment paper.
Bring a large pot of salted water to a boil. Add the gnocchi and cook for 2 to 3 minutes (or according to package directions). Drain the gnocchi then arrange it in a single later on the lined baking sheet. Set it aside to cool for 10 minutes.
In a 13x9-inch baking pan, stir together the cheese, chives and melted butter to form a paste. Spread the paste into an even layer.
Arrange the gnocchi side by side in a single later atop the cheese.
Bake the gnocchi until the cheese turns dark golden, 15 to 20 minutes. Remove the pan from the oven and let it cool completely before serving with marinara sauce for dipping.