Preheat the oven to 400°F. Finely grind nuts in processor. Transfer to a shallow baking dish. Mix mustard, basil, dill and rosemary in medium bowl. Spread mustard mixture over both sides of each chicken breast. Dip chicken breasts into nut mixture, coating completely. Sprinkle with salt and pepper.

Transfer chicken to a baking sheet. Bake chicken until cooked through, about 25 to 30 minutes.