Melt the butter in a large pot over medium heat. Add the chopped onion and celery. Cook for about 4 to 5 minutes, until they are soft and fragrant. Season lightly with salt and black pepper.
Add the diced potatoes, condensed cream of chicken soup, Cheddar cheese soup, and chicken broth. Stir everything together. Sprinkle in the Cajun seasoning, garlic powder, and onion powder. Let the soup simmer gently for about 5 minutes.
Add the chopped rotisserie chicken and cooked bacon. Lower the heat and let the soup simmer for another 15 to 20 minutes. Stir every so often to make sure nothing sticks to the bottom. The potatoes should be tender.
Stir in the sour cream and shredded mozzarella. Mix until smooth and creamy. Remove the pot from the heat.
Ladle into bowls and top with shredded Cheddar, extra bacon, sliced scallions, and crushed buttery crackers before serving.