Slow Cooker Chicken Enchilada Soup

2 boneless skinless chicken breasts (about 1 pound)
2 cups chicken stock
1 1/4 cup (or 1 10-ounce can) red enchilada sauce
2 (14-ounce) cans black beans, rinsed and drained
1 (14-ounce) can diced tomatoes, with juice
1 (15-ounce) can whole-kernel corn, drained
1 (4-ounce) can diced green chiles
2 cloves garlic, minced
1 white onion, peeled and diced
1 teaspoon ground cumin
1 teaspoon salt, or more/less to taste
optional garnishes: chopped fresh cilantro, diced avocado, diced red onion, shredded cheese, sour cream, tortilla strips/chips

DIRECTIONS:

Add all ingredients to a slow cooker, and stir to combine. Cook for 3-4 hours on high heat or 6-8 hours on low heat, until the chicken is cooked through and shreds easily. Use two forks to shred the chicken.

Serve warm, with optional garnishes.

You can also refrigerate in a sealed container for up to 5 days. Or freeze it for up to 3 months.

NOTES:

• I particularly liked the part of the method that had me cook the whole chicken breast and then shred it toward the end.  I simply scooped them out into a bowl to cool a little and they fell apart as I was cutting across the grain.  It was much simpler than trying to cut up the raw meat.
• I used a bigger can of diced tomatoes because that's what I had on hand.
• The original recipe called for a different kind of tomato, but regular ones worked just fine.
• Fwiw, this is gluten free if you're careful on what enchilada sauce is added.