Slow Cooker Chipotle Lentil Soup

• 2 cups lentils, red, rinsed; or brown
• 2 stalks celery, chopped
• 2 carrot, peeled and chopped
• 1/2 onion, yellow; diced
• 3 cloves garlic, minced
• 1 14.5 oz can tomatoes, petite diced
• 1 chipotle pepper, seeded and minced; add additional peppers for extra spice
• 7 cups vegetable broth
• 1 1/2 tsp cumin
• 1 tsp oregano, dried
• salt and pepper, to taste
• 3 tsp adobo sauce, from chipotles in adobo sauce
• 1/4 cup cilantro, minced
• 2 tbsp lime juice

Optional Toppings:

• sour cream
• avocado
• cilantro