In a large pot over moderate heat melt the butter. Add the diced onions and garlic, then cook until fragrant.
Add the potatoes and carrots, then cook until tender.
While still over moderate heat stir in the flour. It will coat the vegetables and combine them with the butter to create a roux.
Add the celery salt, paprika, pepper, cayenne pepper, and mustard powder, then stir to combine.
Add the crushed dill pickle chips and dill pickles, then slowly stir in the dill pickle juice and chicken stock. It will start to thicken slightly as it comes to a boil.
Gently simmer for at least 30 minutes. Check and stir every 10 minutes.
Taste then add water, salt, and pepper to achieve your preferred thickness and flavor. It can be thick like chowder or runny like a traditional soup. Garnish with extra chips or pickle slices.