Slow Cooker Black Bean Soup

Ingredients

• black beans
• peeled and diced sweet potato
• onion
• quart vegetable stock
• ounce can diced or crushed tomatoes
• tablespoons ground cumin
• tablespoon chili powder
• teaspoon salt
• teaspoon garlic powder
• fully cooked rice
• Shredded cheese, sour cream, avocado, optional