Heat oven to 350°F. In medium saucepan, combine wild rice, onion and water. Bring to a boil. Reduce heat to low; cover and simmer 45 to 55 minutes, or until rice is tender and water is absorbed. DO NOT DRAIN.
Add sour cream, soup, thyme, marjoram, salt and pepper to rice mixture in saucepan; blend well. Spread mixture evenly in ungreased 13x9-inch (3-quart) baking dish. Top with asparagus. Place chicken breast halves over asparagus, meaty side up; sprinkle with seasoned salt.
Bake at 350°F. for 1 to 1 1/4 hours, or until chicken is fork-tender and juices run clear.