Easy New England Clam Chowder

Name: Easy New England Clam Chowder
Ingredients: 4 thick slices bacon, chopped; 1 small onion, chopped; 2 stalks celery, diced; 1 clove garlic, minced; 1/2 cup (1 stick) unsalted butter; 2 tablespoons flour; 2-3 cups chicken broth or stock; 1 lb waxy potatoes, peeled and cubed; 1/2 teaspoon dried thyme; 2 (6.5 oz each) cans chopped clams, undrained; 1 (8 oz) bottle clam juice; 2 cups heavy cream; Kosher salt and freshly ground black pepper, to taste; Fresh parsley, minced, for serving (optional); Oyster crackers, for serving (optional)