Combine parsley, salt, onion powder and black pepper in a shallow bowl; mix well. Sprinkle over chicken pieces.
Beat eggs in a shallow bowl with a fork. Beat in mustard until well combined.
Place chopped pecans in a shallow bowl.
Dip chicken pieces in egg mixture, then coat in pecans.
Place chicken on prepared baking sheet. Bake until golden and cooked through, about 15-20 minutes.