Crockpot Chicken, Tomato & White Bean Soup

1 Medium onion, finely chopped
4 Celery stalks, finely chopped
3 Carrots, peeled & finely chopped
1 Tablespoon garlic, minced
1/2 Teaspoon kosher salt
1 Teaspoon black pepper
2 Pounds cooked chicken breast, cut into bite-sized pieces (about 4 cups)
2 Tablespoons butter
3 (14 1/2 oz) Cans chicken broth
2 Cubes chicken bouillon
1 (14 1/2 oz) Can diced tomatoes, drained
1 (14 1/2 oz) Can white beans, drained & rinsed
1/4 Cup finely chopped fresh parsley
1/4 Teaspoon Tabasco sauce (about 2 shakes)

Place the vegetables, garlic, salt, and pepper in crockpot. Top with the chicken pieces, butter, broth and bouillon cubes, Do NOT stir.
Cover and cook on LOW for 7 1/2 hours. Stir in drained tomatoes and beans; continue to cook 1/2 hour more; before serving, stir in parsley and Tabasco sauce.