Bring 1/2 cup chicken stock to a boil and pour over morels. Soak for 1 hour. Drain and then chop mushrooms. Reserve liquid. Pound chicken breasts flat. In small bowl, combine ground chicken, egg, parsley, dill and morels. Place half of the filling on the long side of the chicken breast. Tuck in ends and roll up. Secure with a toothpick. Place chicken rolls in saucepan and add morel soaking liquid, remaining chicken broth and wine. Bring to a boil, reduce heat, cover and simmer for 20 minutes. Remove chicken and set aside. Over medium heat, reduce liquid to 1/3 cup about 15 mintues. Add half and half and simmer for 7 minutes. Off the heat, whisk in butter and vermouth until well blended. Season with salt and pepper. Cut rolls into 1/2 inch slices and spoon sauce over. Serve.