Spray crockpot with cooking spray and add chicken breasts. Note: add ½ cup of water if using fresh chicken, frozen chicken will not need the extra water.
Then add 1/2 tsp of salt, 1/2 tsp of pepper, and 1 tablespoon of Fiesta seasoning. Cook on low for 3-5 hours or high for 2-4 hours. Once chicken is no longer pink, shred chicken apart in the crockpot using a fork or spoon.
Add 1 tablespoon of olive oil to a large pot on medium heat. Add onion and jalapeno to pot and cook for 3-4 minutes until tender.
Add in minced garlic, 1 teaspoon of salt & pepper, cumin, smoked paprika, and 1 tablespoon of fiesta seasoning. Continue to cook for 1 minute.
Add chicken broth and shredded chicken to the pot, cover with lid, and bring to a boil. Once boiling, reduce heat to medium-low and simmer for 15 minutes.
Remove from heat and add fresh lime to soup. Top each serving with avocado, tomatoes, cilantro, and any additional desired toppings.