Prepare Wish-Bone® Italian Dressing & Seasoning Mix according to package directions. Reserve 1/3 cup prepared Dressing & Seasoning Mix; refrigerate remaining for another use.
Bring quinoa, water and salt to a boil over high heat in medium saucepan. Reduce heat to low and simmer covered until liquid is absorbed, about 10 minutes. Remove from heat and let stand covered, about 5 minutes.
Combine cooked quinoa with red onion in medium bowl. Toss with 1/4 cup prepared Dressing & Seasoning Mix. Toss avocados and remaining prepared Dressing & Seasoning Mix in another medium bowl. Gently stir avocado mixture into quinoa mixture. Serve at room temperature or chill, if desired.