Duxelles: Sauté the mushrooms and onion in butter in a frying pan until liquid evaporates. Stir in salt, marjoram, flour, pepper, and broth. Cook, stirring constantly, until mixture comes to a boil and thickens. Remove from heat and stir in parsley and ham. Cool.
Butter Pastry: Combine the flour and salt in a bowl and cut in the butter and the shortening until particles are fine. Add water, 1 Tbs. at a time, to make a stiff dough. Cover and chill.
Beef: Place beef on rack in a shallow baking pan and sprinkle with salt and pepper. Roast at 425 degrees for 30 minutes. Let stand until cool.
Roll butter pastry on a floured surface to rectangle about 3" longer than roast and 12 to 13 inches wide. Press Duxelles into pastry, leaving an inch uncovered on all edges. Place beef on pastry. Moisten pastry edges and enclose beef, pressing edges together firmly. Trim off excess pastry from ends so single layer covers ends of roast. Place roll, seam side down, in a shallow baking pan. Cut decorations from pastry trimmings and place on top. Brush pastry with egg beaten with 1 Tbs. water.
Bake at 400 degrees for 30-35 minutes or until browned. Let stand for 15-20 minutes before slicing.
Notes: The crust and duxelles may be prepared the day before. May use a food processor for both the crust and duxelles. When searing the beef initially, bake it on a wire rack that can fit into a pan to allow any juices to drain off. The second time it goes into the oven, bake it on a cookie sheet or a shallow pan. Use a wide sturdy spatula to lift it onto the serving tray.
