48 small clams, like littleneck or Manila, well rinsed
1 tablespoon olive oil
1 tablespoon butter
2 cups diced onion
2 cups diced leek
Salt and pepper
Pinch cayenne
1 cup diced celery
2 bay leaves
1 large thyme sprig
6 ounces thick-sliced smoked bacon
2 pounds potatoes, peeled and diced
1/2 pound spinach, cooked briefly, squeezed dry and chopped
8 tablespoons crème fraîche
Zest of one small lemon
2 tablespoons chopped dill
1/2 cup thinly sliced scallions