Trim any fat from chicken breasts and cut each in half lengthwise. Place chicken pieces in a bowl and sprinkle with seasoned salt, turning chicken pieces to season all sides.
Place baking mix into a shallow bowl; pour water into a separate bowl. Gently press each seasoned chicken piece into the baking mix, dip quickly in water, and press chicken into baking mix again to coat thoroughly. Dip chicken once more quickly in water and coat a third time in baking mix. Tap off any loose baking mix.
Heat oil in a deep-fryer or large saucepan to 350 degrees F (175 degrees C).
Deep-fry the chicken pieces in batches in the hot oil until the coating is crisp and brown and the chicken is no longer pink inside, about 6 minutes per batch. An instant-read meat thermometer inserted into the thickest part of a breast should read at least 160 degrees F (70 degrees C).
