Place the chicken breasts in a plastic bag (or a ziplock bag) and pound firmly with a meat cleaver or a rolling pin to flatten slightly.
Mix the herbs, salt and pepper along with the crushed nuts in a small bowl and place the mixture on a flat plate. Brush each breast with a thin layer of dijon mustard and coat each side with the herb mixture.
Heat 1 tablespoon olive oil in a saute pan over medium heat. Saute the breasts with the smooth rounded side down for about 3 to 4 minutes.
Reduce the heat to low and turn over the breasts, cooking for another 3 minutes, until cooked through. Remove from the pan and serve.