Melba toast 
noun [mass noun]
Very thin crisp toast.Food is the cheap, no-sweat, low-achievement route to immortality: Melba toast, Caesar salad, tournedos Rossini, Lea & Perrins....
- This Rubenesque singer's love of food and her continual struggle to lose weight eventually led to the creation of Melba toast.
- Hoummos is another favourite, which I like to eat with Melba toast.