Salmon Chowder with Celeriac and Tarragon

Name: Salmon Chowder with Celeriac and Tarragon
Ingredients: 5 cups chopped leeks; 1 cup diced carrots; 1 cup diced celery; 2 tablespoons coconut oil; 4 1/2 cups chopped celery root; 2 cups chopped parsnips; 4 cups clam juice; 6 fresh thyme sprigs; 1 bay leaf; 2 pounds salmon, bones and skin removed, cut into chunks; 1 1/2 cups cashew cream*; 2 tablespoons fresh tarragon, roughly chopped; 2 tablespoons fresh parsley, roughly chopped; 1/2 lemon, juiced; salt and pepper to taste; 1 bunch watercress, to garnish, optional