Sprinkle chicken with seasoned salt and pepper. In a large nonstick skillet, heat oil over medium heat. Add chicken; cook until a thermometer reads 170°, about 6 minutes on each side. Remove from pan; keep warm., In same pan, cook and stir shallots until tender. Add wine; bring to a boil. Cook until wine is reduced by half. Add spinach and salt; cook and stir just until spinach is wilted. Stir in sour cream; serve with chicken. Freeze option: Before adding sour cream, cool chicken and spinach mixture. Freeze in freezer containers. To use, partially thaw in refrigerator overnight. Heat through slowly in a covered skillet, stirring occasionally, until a thermometer inserted in chicken reads 170°. Stir in sour cream.