Chateaubriand is a steak dish made with meat that is cut from a large tenderloin fillet. The dish is usually served with a sauce known as Bearnaise sauce.
The dish was first made by Montmireil, who was the chef of French statesman and author Francois-Rene, vicomte de Chateaubriand. Originally, the dish was prepared from a sirloin cut and served with Chateaubriand sauce. Chateaubriand sauce, which is also occasionally called crapaudine sauce, is made with white wine and shallots that have been prepared with demi-glace and combined with lemon juice, butter and tarragon. Chateaubriand steak is often served with potatoes. The steak is usually broiled or grilled.