Heat oven to 350 F. Spread 2 tablespoons honey mustard in a 13 x 9-inch baking pan. In a medium bowl, combine breadcrumbs, pecans, green onion, garlic and 1/4 teaspoon each salt and pepper. Toss with melted butter to coat mixture.
To make pocket for stuffing, turn each chicken breast half on its side and cut a 3-inch long slit in the thickest part. Cut as deeply as possible without slicing completely through the chicken. Divide pecan stuffing mixture among chicken breast halves, filling each pocket generously so it mounds slightly.
Arrange chicken pieces, stuffing side facing up, in prepared baking pan. Brush remaining 2 tablespoons honey mustard on outside of each piece of chicken. Sprinkle with remaining 1/4 teaspoon salt and pepper; bake 30 minutes or until cooked through and stuffing is golden brown. Just before serving, spoon pan juices over chicken.
Nutrition information serving – calories: 333; protein: 18g; carbs: 17g; saturated fat: 5g; monounsaturated: 11g; polyunsaturated fat: 4g; cholesterol: 52 mg; fiber: 3g; sodium: 696 mg.