1. Prepare the Chicken and Vegetables: Start by placing the boneless, skinless chicken breasts or thighs at the bottom of your slow cooker. Evenly distribute the chopped yellow onion, sliced carrots, and sliced celery over the chicken.

2. Add the Frozen Vegetables and Tomatoes: Next, add the frozen corn, frozen green beans, and the can of diced tomatoes (including their liquid) into the slow cooker, spreading them over the fresh vegetables.

3. Pour in the Broth and Seasonings: Carefully pour the low-sodium chicken broth over all the ingredients. Sprinkle in the dried Italian seasoning, garlic powder, and black pepper. Stir gently to combine the seasonings with the broth and vegetables, ensuring everything is well distributed.

4. Set and Cook: Cover your slow cooker with its lid. Cook on the “low” setting for 6-8 hours, or on the “high” setting for 4-6 hours. The soup is ready when the chicken is cooked through and easily shreds, and the vegetables are tender.

5. Shred the Chicken: Once the cooking time is complete, carefully remove the cooked chicken breasts or thighs from the slow cooker. Place them on a cutting board and use two forks to shred the chicken into bite-sized pieces.

6. Return Chicken and Adjust Seasoning: Return the shredded chicken to the slow cooker and stir it into the soup. Taste the soup and add salt as needed, starting with a quarter teaspoon and adding more until it reaches your desired flavor.

7. Serve Warm: Ladle the hot soup into bowls. If desired, garnish each serving with fresh chopped parsley for a touch of color and freshness. Serve immediately and enjoy your wholesome meal.