Preheat the oven to 190°C/375°F to ensure even baking.
Cook the gnocchi according to packet instructions until they float, then drain and set aside.
In a large saucepan over medium heat, melt 2 tablespoons of truffle butter. Whisk in the flour for a couple of minutes before gradually adding milk, continuing to whisk until thickened into a rich sauce.
In a food processor, combine the remaining truffle butter, breadcrumbs, parmesan, garlic, and parsley. Blend until mixed thoroughly.
Add cheddar and additional parmesan to your thickened sauce, stirring until completely melted. Season generously with salt and pepper before mixing in cooked gnocchi.
Transfer your gnocchi mixture into a baking dish and evenly sprinkle on the breadcrumb topping. Bake in the preheated oven for 10-15 minutes or until bubbling and golden brown on top.