Heat the oven to 482°F (250 °C). Oil a baking tray. Mix the chopped pistachios and breadcrumbs.
In a separate bowl, combine the oil, honey, mustard, salt and black pepper. Cut the chicken breasts into slices and dip them in the spice mixture first, then in the pistachio mixture.
Arrange them in the oiled tray and put them in the heated oven, reducing the heat to 374°F (190 °C). Bake until the crust browns.