Cook the Bacon and Aromatics
In a large Dutch oven or heavy pot, cook diced bacon over medium heat until crispy.
Remove bacon with a slotted spoon, leaving 2–3 tbsp bacon fat in the pot.
Add onion, carrots, and celery; sauté 5–7 minutes until softened.
Stir in garlic and cook 1 minute more.
Make the Roux and Broth Base
Sprinkle flour over the vegetables; stir 1–2 minutes until lightly toasted (no raw flour smell).
Gradually whisk in chicken broth and reserved clam juice until smooth and lump‑free.
Add milk, cream, diced potatoes, bay leaf, thyme, salt, and pepper.
Bring to a light boil, then reduce to a gentle simmer.
Simmer the Chowder
Cover and simmer 15–20 minutes, stirring occasionally, until potatoes are tender and the broth thickens slightly.
Do not boil hard after adding dairy to avoid curdling.
Add Clams and Finish
Stir in drained clams and cooked bacon; simmer 3–5 minutes just to heat through (do not overcook to keep clams tender).
Taste and adjust seasoning; add a small splash of extra clam juice if desired for salinity.
Remove bay leaf and thyme sprig. Stir in fresh parsley.
Serve
Ladle into bowls and serve with oyster crackers and a crusty bread or bread bowl if desired.