In your slow cooker combine chicken, peas, corn, carrots, celery, potatoes, onions, cream cheese, chicken broth, chicken bouillon, and garlic powder. Cover and cook on low for 4-6 hours. (Chicken should be cooked through and potatoes should be easily pierced with a fork)
About 30 minutes before serving shred chicken with two forks and stir in heavy cream and salt and pepper to taste.
Bake biscuits according to package's instructions.
Serve bowls of soup topped with a biscuit or two and fresh thyme if desired.
For a thicker soup, 2 cups of heavy cream can be replaced with two cans of cream of chicken or cream of mushroom soup.