Light your fire and let it burn down for 1 hour until you have nice coals. (Or use hardwood charcoal.)
Put the clams in a large Dutch oven, add about 4 cups ocean water, then set over medium–high heat. Cover and cook for 10–15 minutes or until the clams have opened. (Any clams that fail to open should be discarded.) Strain the clam broth through a sieve lined with cheesecloth or doubled-up paper towels and reserve for later. Remove the clams from the shells and set aside.
Cook the bacon over the coals for 4 minutes or until cooked to your liking, then cut into any size you like.
Rinse out the pot and return it to the heat. Add the butter and let it melt, then add the leek and cook, stirring frequently, for 10 minutes or until softened but not browned. Stir in the potatoes and wine and cook for another 5 minutes or until the wine has evaporated and the potatoes have just started to soften. Pour in enough of the clam broth to just cover the potatoes (about 3 cups) and add the thyme sprigs and bay leaf. Partially cover the pot and simmer gently for a further 10–15 minutes, or until the potatoes are tender.
Meanwhile, roughly chop the clams.
When the potatoes are nice and tender, add the cream and stir in the chopped clams and bacon. Season to taste. Bring to a simmer, then remove the pot from the heat. (You don’t want the chowder to come to a full boil.) Fish out and discard the thyme sprigs and bay leaf.
The chowder should be allowed to sit for a while to cure, at least 2 hours. Gently reheat before serving. Sprinkle with parsley and serve with crackers on the side.