Begin by rinsing the oysters thoroughly under cold water to remove any grit. Once clean, carefully shuck the oysters or, if using jarred oysters, simply drain them and reserve the oyster juice. Roughly chop the oysters into bite-sized pieces and set them aside.

In a large pot, heat 2 tablespoons of bacon fat or butter over medium-high heat until melted and fragrant. Add the diced potatoes, celery, and shallots, sautéing for about 2-3 minutes until they become softened and slightly translucent.

Lower the heat to medium and sprinkle in the all-purpose flour, Old Bay seasoning, and salt. Stir continuously for about 1 minute, allowing the flour to toast lightly while absorbing the flavors.

Gradually pour in the reserved oyster juice while scraping the bottom of the pot to lift any browned bits. Stir well to ensure the mixture is smooth and combine with the sautéed ingredients.

Slowly pour in the warmed whole milk, stirring continuously to blend everything together. Allow the stew to simmer gently for about 15 minutes.

Once the potatoes are cooked through, gently fold in the chopped oysters into the simmering stew. Cook for an additional 2-3 minutes until the oysters are heated through.

Ladle the creamy oyster stew into warm bowls and garnish with freshly chopped parsley. Serve with hot sauce and soda crackers on the side.