In a heavy soup pot, bring the oyster liquor and potatoes to a boil and cook over medium heat until potatoes are tender, about 10 minutes.

Meanwhile, in a heavy saucepan over medium heat, melt the butter and sauté the onion, leeks, celery, bay leaves, and garlic until very soft. Make a roux by adding the flour and stir for 2-3 minutes until the flour is cooked; do not let the roux brown.
Gradually stir in about 2 cups of the liquid from the cooked potatoes until the roux is incorporated.
Pick out the bay leaves and discard, and add this mixture back to the pot with the potatoes, season to taste with salt and pepper, bring to a simmer.
Add the oysters, and cook for 5–10 minutes until the oysters begin to curl around the edges and are barely done.

Remove from heat and serve with a crunchy green salad and plenty of hot French bread for dipping.

A hearty soup for cold Louisiana winter days.