Slow Cooker Black Bean Soup

So my slow cooker is my new toy, hence the multiple slow cooker posts this week. This soup is super easy, tasty, and healthy. I've frozen it in individual lunch size servings so I can just pop it in the microwave at work. It made five individual servings. (Got the recipe from Smitten Kitchen.)

Ingredients:
1 tbsp olive oil
2 medium size red onions, chopped
1 medium size red bell pepper, chopped
1 medium size green bell pepper, chopped
4 garlic cloves, minced
4 tsp ground cumin
1 16-oz package dried black beans
1 tbsp chopped chipotle chiles, from a can
7 cups hot water
2 tbsp lime juice
2 tsp kosher salt
1/4 tsp ground black pepper