- 1 cup mayonnaise
- 2 cups shredded Swiss cheese
- 1/2 cup grated Parmesan cheese
- 2 cups thinly sliced Vidalia sweet onion
- hot sauce, or to taste
- Preheat oven to 350 degrees F (175 degrees C).
- Stir the mayonnaise, Swiss cheese, Parmesan cheese, Vidalia onion, and hot sauce together in a casserole dish.
- Bake in the preheated oven until the edges are golden brown, 30 to 35 minutes. Allow to cool 10 minutes before serving.