Stir together the pecans, bread crumbs, and 2 tablespoons of clarified butter. Spread the mixture out on a plate. Press the chicken breasts into the mixture to coat on both sides. Heat the remaining 2 tablespoons of clarified butter in a large skillet over medium heat. Place the coated chicken breasts in the pan, and fry on both sides until nicely browned and chicken meat is cooked through, about 10 minutes per side.
In a small saucepan, whisk together the Dijon mustard, brown sugar, bourbon, soy sauce, and Worcestershire sauce until smooth. Bring to a simmer over medium-low heat, then remove from the burner, and whisk in the 3/4 cup of unsalted butter one piece at a time. Do not return to the heat.
Arrange the chicken breasts on a large serving plate. Pour the sauce over the chicken, and sprinkle with green onion.