In a large heavy-bottomed pot or Dutch oven, cook the chopped bacon over medium heat until crispy and golden brown, about 6-8 minutes.

Remove the bacon with a slotted spoon and set aside on a paper towel, leaving about 2 tablespoons of bacon fat in the pot.

Add the diced onion and celery to the pot, sautéing over medium heat until the vegetables are softened and translucent, about 5 minutes.

Stir in the minced garlic and cook for another minute until fragrant, being careful not to burn it.

Sprinkle the flour over the vegetables and stir constantly for 1-2 minutes to cook out the raw flour taste and create a roux.

Slowly whisk in the bottled clam juice, the reserved juice from the canned clams, and the chicken broth, ensuring there are no lumps.

Add the cubed potatoes, dried thyme, and bay leaf, then increase the heat to bring the mixture to a gentle boil.

Reduce the heat to low, cover, and simmer for 15-20 minutes, or until the potatoes are fork-tender.

Stir in the chopped clams and half-and-half, and heat gently for 3-5 minutes until warmed through; do not let the soup boil or the dairy may curdle.

Discard the bay leaf, taste the chowder, and season with salt and generous amounts of black pepper as needed.

Ladle the hot chowder into bowls and top with the crispy reserved bacon and fresh parsley before serving with crusty bread or oyster crackers.