Sprinkle chicken evenly with salt, pepper, and, if desired, seasoned salt.
Melt butter in a large skillet over medium heat. Add chicken pieces, and cook 5 minutes on each side or until browned. Remove chicken; keep warm.
Add onions to skillet, and sauté 10 minutes or until tender. Return chicken to skillet; stir in 1/2 cup water, cover, and simmer, stirring occasionally, 30 minutes or until sauce thickens and chicken is done. Serve over hot cooked rice.