1 pound skinless, boneless chicken breasts, cut into 3/4-inch pieces
1 cup half-and-half
3 tablespoons tawny port or dry sherry
2 tablespoons finely chopped flat-leaf parsley
In a medium saucepan, bring the chicken stock to a boil with the dried mushrooms. Cover the saucepan and remove from the heat.
Melt the butter in another medium saucepan. Add the onion and cook over moderately high heat, stirring occasionally, until softened, about 3 minutes. Add the sliced cremini and cook until tender and their liquid has evaporated, about 5 minutes. Season the cremini with salt and white pepper and stir in the flour. Strain the stock into the saucepan, pressing hard on the solids with the back of a spoon. Stir the soy sauce into the mushroom soup, cover partially, and simmer until slightly thickened, about 10 minutes.
Transfer half of the mushroom soup to a blender or food processor and puree until smooth. Return the puree to the saucepan. Add the chicken pieces and simmer the soup until the chicken is cooked through, 3 to 4 minutes. Stir in the half-and-half and port and simmer the soup for 1 minute longer. Stir in the parsley, ladle the soup into bowls and serve right away.