The final piece is kind of this rich, velvety, slightly tangy gravy ... of *** burger sauce. It's our version of *** slightly less tangy 1000 islands. Some fresh cooked bacon, sharp white cheddar ...

The burger chain’s new White Truffle Burger sounds promising enough — a Fontina cheeseburger, topped with a “real white truffle sauce made with Regalis organic white truffle oil ...