Rich, smoky bacon-flavored chowder with tender chunks of clams and colorful sweet potatoes: here's a hearty, feel-good meal that will warm you all the way to your toes. And making your own clam chowder is easier than it sounds.
1. Scrub the clams well. Spread them in an even layer in a large 12-inch frying pan with a lid. Add the water, cover, and bring to the water to a boil. Set a heatproof bowl nearby to hold the cooked clams. Cook the clams until the shells open, about 2 to 5 minutes. As a clam opens, remove it from the pan with tongs and plop it into the waiting bowl. Give the clams 5 minutes more to cook, transferring clams as they open. After 5 minutes, turn off the heat and discard any clams that remain closed. Pour the pan liquid through a fine-meshed sieve or cheesecloth to strain out any grit. You should have about 1 1/2 cups clam cooking liquid. If there is less than that, add enough bottled clam juice to equal this amount. Set the liquid aside. Transfer the clams, still in their shells, back to the pan and cover it with a lid to keep the clams from drying out while you finish the chowder.
2. Cook the bacon in a 3-quart soup pot until crisp and brown. When the bacon is done transfer to a paper-towel lined plate to drain, reserving 1 tablespoon of the bacon fat in the pot. Discard the rest of the bacon fat. Using the same soup pot in which you cooked the bacon, pour back in the 1 tablespoon of bacon fat, add the olive oil and heat over a medium flame for a few seconds; add the onion and celery. Cook vegetables until soft and golden, about 5 minutes. Add the sweet potatoes, clam cooking liquid, the bay leaf, salt and pepper. (Save the cooked bacon to sprinkle over the chowder just before serving.) Cover the pan and simmer just until the sweet potatoes are tender, 8 to 10 minutes.
3. While the chowder simmers, remove the clams from their shell. You can use a paring knife or even a grapefruit spoon to scrape them out of their shells and into a bowl. Discard the shells. When the sweet potatoes are perfectly done, add the clams to the chowder. Pour in the Half and Half, heat gently until the chowder is piping hot, and ladle it into individual serving bowls. Sprinkle bacon around the edge of the chowder and serve.