Preheat your oven to 375 degrees Fahrenheit. This is an important step to ensure your dish is perfectly baked and bubbling by the time it’s ready to serve.
Cook the gnocchi according to package directions until they are al dente. This should take just a few minutes. Once they are cooked, drain them and set aside. Make sure they are not overcooked, as they will continue to soften in the oven.
While the gnocchi is cooking, you can start preparing the cheese sauce. In a large saucepan or Dutch oven, melt 3 tablespoons of truffle butter over medium heat. The aroma will be heavenly! Once melted, add the flour and whisk to combine. Cook this mixture over medium-low heat for about 3 to 4 minutes, whisking frequently until it turns a light brown color. This is your roux, and it’s crucial for thickening the sauce.
Gradually add the milk to the roux while whisking continuously. This helps avoid lumps. Cook over medium heat for about 5 to 10 minutes, or until the sauce starts to thicken. You’re looking for a smooth, creamy consistency.
While the sauce is thickening, melt the remaining tablespoon of truffle butter in a separate pan. Add the bread crumbs, 2 tablespoons of parmesan cheese, the melted butter, the garlic clove, and the parsley into a food processor. Process for about 30 seconds until the mixture is minced. This will create a delicious topping that adds crunch to your baked dish.
Once your sauce has thickened, remove it from heat and stir in the swiss cheese, white cheddar, and the remaining parmesan cheese. Stir until all the cheese is completely melted and the sauce is smooth. Season it with kosher salt and white ground pepper for flavor.
Add the drained gnocchi to the cheese sauce and stir gently to combine. Make sure all the gnocchi are coated in that creamy sauce.
Pour the mixture into an 8x8-inch baking pan or a 1-quart casserole dish. Ensure it’s evenly spread out. Now, sprinkle the breadcrumb mixture on top, adding a beautiful crunchy layer that contrasts with the creamy gnocchi.
If desired, sprinkle additional parmesan cheese on top of the breadcrumbs for an extra cheesy finish. Bake in the preheated oven for about 10 to 15 minutes, or until the top is lightly browned and bubbly. The aroma will be incredible!
Once baked, serve immediately while it’s hot and bubbly. Enjoy the harmonious blend of flavors in every bite!