Best Chicken Pasta Salad

2 boneless, skinless chicken breast halves
3/4 cup steak sauce
1 (12 ounce) package fusilli pasta
2 cubes chicken bouillon
1 Vidalia onion, diced
2 avocados - peeled, pitted and diced
1 cup halved cherry tomatoes
1 cup Ranch-style salad dressing

Preheat an outdoor grill for high heat. Place breasts into a glass baking dish and marinate in steak sauce for 15 to 60 minutes.
Grill chicken until no longer pink and the juices run clear. Remove from grill, and chop into bite-size pieces.
To a large pot of boiling water, add bouillon cubes and pasta. Cook pasta until al dente. Drain, and rinse under cold water.
In a large bowl, combine chicken, pasta, onion, avocados and tomatoes. Mix in salad dressing, cover, and refrigerate until chilled.