05Transfer prosciutto-topped steaks to a serving dish. Add remaining 1 tablespoon butter to the skillet and when it melts add shallots. Cook briefly, stirring, and add mushrooms. Cook, stirring, about 2 minutes.06Add chicken broth and stir. Cook about 1 minute over relatively high heat.07Meanwhile, cover prosciutto-topped steaks with equal portions, and in one layer, of cheese. Run briefly under the broiler until cheese melts. Pour mushroom mixture over the cheese and serve hot.