Cook the Bacon: In a large Dutch oven over medium heat, add the chopped bacon. Cook until crispy and golden brown, about 7-10 minutes. Use a slotted spoon to transfer to a paper towel-lined plate, leaving the fat in the pot.

Sauté the Aromatics: In the same Dutch oven with the bacon fat, melt 2 tablespoons of butter over medium heat. Add diced celery, leek, and onion, stirring occasionally until they soften, about 5-7 minutes. Add minced garlic during the last minute.

Add the Potatoes and Broth: Incorporate cubed potatoes to the sautéed veggies, stirring well. Pour in 4 cups of broth, then season with salt, white pepper, and dried thyme. Bring to a boil, then reduce heat to medium-low and cover, simmering for 10-15 minutes until potatoes are tender.

Thicken the Chowder: In a separate bowl, whisk together 1/4 cup of flour and 2 cups of half-and-half until smooth. Gradually stir this mixture into simmering chowder. Continue stirring and cook for an additional 1-2 minutes until thickened.

Stir in the Clams: Add chopped clams and optional clam juice, stirring gently. Pour in remaining half-and-half and heat through on low for about 5 minutes, avoiding boiling.

Add Bacon and Bay Leaf: Mix in crumbled bacon and bay leaf, stirring to blend. Simmer for another 2-3 minutes.

Serve with Fresh Garnish: Remove bay leaf and serve hot. Garnish with extra crumbled bacon and a sprinkle of chives or green onions.