Make the clam broth (Simply submerge the clams under 3 cups of water. Use a wide stockpot so clams are not overly stacked on one another. Boil until clams open. Sieve the broth into another pot. It should be grey, cloudy, and brine-y. Craig says it should make your mouth pucker!)
Heat the bacon in a medium stockpot over low heat until a few tablespoons of fat render out. Rain the heat to medium and brown the meatier pieces, being careful not to burn them. Remove and reserve the browned pieces but leave the fat in the pot. Before serving the chowder, you can reheat the crispy browned cracklings from the salt port or the bits from the bacon and add them as a topping.
Add the butter, if needed, for additional cooking fat. Add the onion, celery, thyme, bay leaf, oregano, and red pepper flakes. Sauté 5 to 7 minutes over medium heat, until the vegetables are softened. Add the garlic last minute.
Add 3 cups of the clam broth, tomatoes, and tomato paste and bring to a boil.
Add the potatoes, cover the pot, and simmer for 10 to 12 minutes, or until the potatoes are cooked through.
Add 1 cup of the heavy cream and taste. Add up to 1 more cup of heavy cream to desired taste. Remove the pot from the heat.
Chop the clams roughly into quarters or halves and stir into the chowder. Leave a few of the smaller clams whole, if desired.
Ladle into individual bowls and add optional seasonings to taste.