Trim the filet nicely, removing the outer muscular skin. Lard the Filet well, using larding needles. The lard must be very thin like a shoestring. The larding is done by filling the needles with the lard and pushing them through the Filet as far as they will go. If the needles are long enough, they will come out on the other side of the Filet, leaving the lard within. Repeat this process all down the center and along the sides of the Filet, about an inch apart, and have the rows neat and even. If you have not a larding needle, make incisions with a knife, and push the lard in with your finger, but the Filet is never as juicy and tender, nor does it look so clean and even when baked. When well larded, dredge well with salt and pepper, rubbing this thoroughly into the Beef. Cut up one small onion, one bay leaf, and mash four cloves, and place in the bottom of the baking pan. Lay the larded Filet on this bed, the larded side being uppermost. Put small bits of butter equal to a half tablespoonful on top, and bake at 400 degrees for one and one-half hours, allowing fifteen minutes per pound. This dish is always eaten rare. To ascertain if sufficiently done, stick a fork into the Filet; if the blood bubbles out, it is ready to serve. The meat, when done, is always spongy and elastic to the touch.
In the meantime, prepare the following Brown Sauce: