Preparation Cook bacon in a 4- to 5-quart heavy pot over medium heat, stirring, until slightly browned but not crisp. Chop white and pale green parts of scallions (reserve greens) and add to bacon along with 1 tablespoon butter. Cook, stirring, 2 minutes. Stir in corn, potatoes, clam juice, water, and 1/2 teaspoon pepper and bring to a rolling boil, uncovered. Add clams and return to a boil, then simmer, uncovered, stirring occasionally, until clams are just opened wide, 5 to 8 minutes (discard any clams that remain unopened after 8 minutes). Chop 1/2 cup scallion greens and add to chowder along with milk, cream, and remaining tablespoon butter. Cook, stirring, until heated through (do not let boil). Season with salt and pepper.
Preparation Cook bacon in a 4- to 5-quart heavy pot over medium heat, stirring, until slightly browned but not crisp. Chop white and pale green parts of scallions (reserve greens) and add to bacon along with 1 tablespoon butter. Cook, stirring, 2 minutes. Stir in corn, potatoes, clam juice, water, and 1/2 teaspoon pepper and bring to a rolling boil, uncovered. Add clams and return to a boil, then simmer, uncovered, stirring occasionally, until clams are just opened wide, 5 to 8 minutes (discard any clams that remain unopened after 8 minutes). Chop 1/2 cup scallion greens and add to chowder along with milk, cream, and remaining tablespoon butter. Cook, stirring, until heated through (do not let boil). Season with salt and pepper.