1Make the cheese sauce: melt butter in a pan, add flour, mix, add milk, mix until smooth, add salt, pepper, truffle pesto, garlic powder, red leicester and cheddar cheese, mix until melted and creamy.
2Prepare the chicken: butterfly the chicken breast, season with salt, pepper, and garlic powder. Dip in the flour, egg, then breadcrumbs and parmesan.
3Fry the chicken in oil for about 4 minutes per side.
4Make the tomato sauce: chop garlic and saute in oil. Add passata, salt, pepper and fresh basil.
5Assemble the sandwich: spread tomato sauce on bread, layer with sliced chicken, mozzarella cheese, mac and cheese, chives, crispy onions, and top with extra cheese sauce.