Mine requires spinach, prosciutto, grated Romano cheese, butter, mushrooms, garlic and salt and pepper to taste. Sorry, no quantities, I eyeball everything, and this recipe’s quantites are mostly determined by individual preference, anyway.
Pull the stems from the mushrooms and mince along with the garlic. Roll several leaves of spinach together and slice; this will make strips crosswise against the leaves. Saute all these together in butter with salt and pepper. Add chopped prosciutto at the end after the garlic and spinach has softened. Stuff the 'shrooms, top with the grated romano, and pop under the broiler until the cheese browns. Serve immediately.