Cut lengthwise from a well-trimmed tenderloin of beef half-heart-shaped pieces, five by two and one half inches, and half an inch thick. Beat these lightly with a web cutlet bat, and with a sharp knife trim neatly to an exact pattern laid on the meat. Lard on one side with rows of fine lardoons, season with salt and pepper, and sauté in oil or clarified butter four minutes on the larded side and the same length of time on the other. For plain grenadins, remove from the pan and serve with clear beef gravy (standard broth) poured over them. To serve Beaumarchais style, drain off or add to the butter in the pan as needed, add a teaspoonful or more of fine-chopped, blanched and drained shallot, and sauté without coloring; add flour, stock, and seasoning as needed, also egg yolks and lemon juice, and strain on to a serving dish: sprinkle with fine-chopped parsley and arrange the grenadins above, one overlapping another, straight down the dish, surround with croustades, equal to the number of grenadins, filled with mushrooms stewed in cream.