Beef Wellington is a steak dish of English origin, made out of fillet steak coated with pate (often pate de foie gras) and duxelles, wrapped in puff pastry, then baked. Some recipes include wrapping the coated meat in a crêpe or dry-cured ham to retain the moisture and prevent it from making the pastry soggy. A whole tenderloin may be wrapped and baked, and then sliced for serving, or the tenderloin may be sliced into individual portions before wrapping and baking.

Source: Wikipedia