Dungeness Crab Bisque

Name: Dungeness Crab Bisque
Ingredients: 4 Dungeness crabs; 3 tablespoons olive oil; 1 carrot, chopped; 2 stalks celery, chopped; 3 tomatoes, chopped; 5 cloves garlic, chopped; 5 shallots, chopped; 3 sprigs fresh tarragon leaves, chopped; 3 tablespoons Cognac; 2 cups dry white wine; 2 tablespoons tomato paste; 10 cups fish stock or water; Salt; Freshly ground pepper; Cayenne pepper; Pinch dried thyme; 1 bay leaf; 2 cups heavy cream; 1 lemon, juiced; 1 tablespoon minced chives or parsley leaves