Heat vegetable oil in a large saucepan over medium heat, stir in mushrooms and carrot and cook and stir until mushrooms start to give up their liquid and carrot begins to soften, about 5 minutes. Add grated turkey, onion powder, salt, pepper, bay leaf and sherry to the pan and cook, stirring, another 5 minutes to reduce pan juices and cook away the alcohol from the wine.
Pour the soup over the turkey mixture and bring to a boil. Reduce heat and add the cream, parsley and frozen peas. Simmer 5 to 10 minutes to reduce the sauce and heat the peas through. Remove bay leaf and stir in butter just before serving.