Cook bacon in a large Dutch oven over medium heat until crisp. Remove from pan, reserving 1 tsp drippings in pan. Crumble & set aside.
Add onion, celery, salt, thyme & garlic to drippings in pan; cook 4 minutes or until vegetables are tender.
Drain clams, reserving liquid. Add clam liquid, potato, clam juice and bay leaf to pan; bring to a boil. Reduce heat and simmer 15 minutes or until potato is tender. Discard bay leaf.
Combine milk & flour, stirring with a whisk until smooth. Add flour mixture to pan; bring to a boil. Cook 12 minutes oruntil thick, stirring constantly.