Cook the chicken breasts by simmering them in the chicken stock for 10 to 15 minutes.
Remove them and set them aside.
Saute the almonds in the butter over moderate heat until golden.
Place the almonds, onion, and one of the chicken breasts in an electric blender or food processor, along with a little of the stock, and blend until pureed.
Add this mixture to the remaining stock, along with the nutmeg, cumin, and cayenne.
Add the second chicken breast, cut into small pieces, and heat over moderate heat, stirring occasionally.
Add the optional sherry just prior to serving.
Taste and adjust the seasoning.
Garnish with the chopped parsley.