Preheat a grill.
Mix marinade ingredients in a baking pan. Add salmon, turn to coat, and marinate for 10 minutes.
Preheat the oven to 400 degrees F.
In a small bowl, mix walnuts, croutons, oregano, chives, olive oil, and lemon juice. On a grill, place salmon meat side down for 4 minutes or until seared. Remove and place on foil lined baking sheet, skin side down. Lightly brush with marinade. Sprinkle crust on top. Bake for 4 to 8 minutes, or until the salmon is cooked to the desired doneness and the crust is golden.