Cook the chopped bacon in a large Dutch oven or heavy soup pot over medium heat for 6-8 minutes, until crisp. Transfer it to a paper-towel-lined plate and leave about 2 tablespoons of bacon fat in the pot, discarding any excess.

Add the diced onion and celery to the bacon fat. Cook for 5-7 minutes, stirring occasionally, until the vegetables soften, then add the minced garlic and cook for about 30 seconds.

Sprinkle the flour over the vegetables and stir continuously for 1-2 minutes. This creates a light roux and cooks away the raw flour taste.

Gradually whisk in the chicken broth, scraping the bottom of the pot to loosen any browned bacon bits. Continue whisking until the broth is smooth.

Add the potatoes, about half of the corn, kosher salt, black pepper, thyme, and bay leaf. Bring the mixture to a gentle boil, reduce the heat, and simmer uncovered for 15-20 minutes, or until the potatoes are tender.

Stir in the remaining corn and half-and-half. Simmer gently for 5-8 minutes, until the chowder is heated through and slightly thickened, taking care not to let it boil vigorously after adding the dairy.

Remove the bay leaf and taste the chowder, adjusting the salt and pepper as needed. For a thicker texture, mash some potatoes against the side of the pot or briefly blend 1-2 cups of soup with an immersion blender before stirring it back in.

Ladle the chowder into bowls and top with the reserved crisp bacon and chopped parsley or chives. Serve hot with your favorite crusty bread or oyster crackers.