Dip your chicken in flour and then brown in butter in a frying pan over medium heat.
Arrange chicken in a buttered 13x9x2 inch baking dish.
Top each piece of chicken with 1 slice of proscuitto and a half slice of cheese.
Cook shallots and garlic until soft.
Add mushrooms, wine, broth and herbs and bring to a boil. Cook 10 minutes.
Add 1 Tbsp. flour and small amount of sherry (you'll be using the rest of the sherry later).
Once that has been well mixed stir in the remaining sherry and cream.
Season with salt and pepper to taste and stir.
Pour sauce over chicken and bake for 20 minutes at 375 degrees.