Warm the pot over medium heat and fry the bacon until the fat renders and the bacon starts to crisp. Add the onion and cook until it's translucent. Stir in the flour and cook it until the mixture is lightly browned and has a slightly nutty flavor. If you can still taste flour, it's not ready.
Gradually whisk in clam broth and the reserved clam juice from clams. Add potatoes, bay leaf, and thyme. Simmer until the potatoes are tender, about 10 minutes. (Optional: Mash the potatoes a bit with a potato masher to help thicken the soup even more.)
Add the clams, corn, cream, parsley, salt (taste first, may not be necessary) and ground pepper to taste. Bring to a simmer and cook for about 30 minutes. Remove from heat and serve garnished with parsley and oyster crackers or in a bread bowl.