Step by step

Cut some thin slices of raclette cheese and arrange them on one side of the chicken breasts

Tips
Chicken breast meat is a light and healthy, rich in proteins: if you prefer not to make it heavier with butter while cooking, use olive oil instead.
Trivia
Walnuts, in ancient times, were considered to be rather indigestible and therefore kept only for animals; more recently it is their important function in protecting against bad cholesterol which has been emphasised.