Slow Cooker Chicken Tortilla Soup

• 1 3/4 lbs boneless skinless chicken thighs, or chicken breasts (trim thighs of excess fat)
• 2 (14.5 oz cans) low-sodium chicken broth
• 1 (14.5 oz) can fire roasted diced tomatoes
• 1 (8 oz) can tomato sauce
• 1 (4 oz) can chopped green chilies
• 3/4 cups finely chopped yellow onion, rinsed under hot water to remove harsh bite
• 1 Tbsp minced garlic, rinsed under hot water to remove harsh bite
• 1 Tbsp chili powder
• 2 tsp ground cumin
• 1 tsp paprika (sweet or smoked)
• Salt and freshly ground black pepper, to taste
• 1 (14.5 oz) can black beans, drained and rinsed
• 1 1/2 cups frozen corn
• 1/4 cup chopped fresh cilantro

For serving (optional):

• tortilla chips, crushed
• Shredded cheddar or Monterey Jack cheese
• Diced avocado , diced roma tomatoes, sour cream (optional)