Step 1 Heat a large, heavy-bottomed pot over medium-high heat. Add the oil, shallot, leek and potato, and cook, stirring constantly, until the leek is translucent, 3 to 5 minutes. Stir in the garlic, clams and add the wine. Continue to cook, scraping any flavoring from the bottom of the pan, until the wine is reduced by half, about 10 minutes.
Step 2 Stir in the cream, thyme and parsley, and bring to a simmer. Reduce the heat to a gentle simmer and continue to cook until the clams are opened and the potatoes are tender, 10 to 12 minutes. Taste and season as desired with salt and pepper.
Step 3This makes about 3 quarts soup. Garnish each serving with 2 chive blossoms or a sprinkling of minced fresh chives.