1. Prepare the parmesan chips. Heat a pan, then when it is hot, make "pancakes" with parmesan. Cook until golden brown, season with salt and pepper, and set aside on paper towels. You don't have to cook the chips on both sides, unless they are thick enough. You can also make these chips in the oven.
2. Prepare your sauce by mixing mayonnaise and pesto.
3. Cut your burger buns in half and toast the inside in a pan with a knob of butter.
4. Remove the buns from the pan, then cook your patties for 3 minutes on one side. When you "flip" your patty, place slices of mozzarella on the already cooked side so that it melts slightly.
5. While your patties are cooking, spread a spoonful of sauce on the toasted sides of the buns. On the bottom bun, place arugula on the sauce, then add a few slices of tomatoes, followed by a parmesan chip. Place the patty covered with melted mozzarella on top, then add some onion slices and basil leaves. Close with the top bun. Serve with homemade fries or coleslaw!