Rinse and trim the chicken breasts. Pat dry. Generously coat both sides of each breast with sour cream. Put crushed cornflake crumbs in a shallow plate or bowl and season to taste (I use onion salt and garlic salt). Dip the sour cream coated chicken in the seasoned cornflake crumbs.
Place coated chicken in a lightly greased 9×13 inch baking dish. Drizzle with melted butter/margarine and bake in the preheated oven for 1 hour.