Wash/clean chicken breasts. Melt enough butter to coat your breasts (1/2 stick usually covers 3 large breasts). I put the butter in a bowl, and melt in microwave.
Get a flat plate, and pour a pile of breadcrumbs onto the center (sorry, I don't use a measuring cup), perhaps 2 cups.
Add about 1 cup grated parmesan cheese to the breadcrumbs, and mix together until well blended.
Coat chicken breast into melted butter, then cover with breadcrumb/parmesan cheese mixture, and place on baking sheet. (No need to spray the sheet; but, lining it with aluminum foil makes for easy cleanup!)
Continue until all breasts are coated, and bake for 1 hour in preheated oven. Use less time if breasts are thin chicken tenders or cutlets.