place porcini mushrooms in food processor or mini chopper; process until finely ground. Combine ground mushrooms, oil, cheese, pepper, and garlic in small bowl. Press mixture evenly onto all surfaces of beef roast.
prepare grill for indirect cooking by igniting an equal number of charcoal briquets on each side of the fire grate, leaving open space in center. when coals are medium, ash-covered (bout 25-30minutes), add 3-4 new briquets to each side. place aluminum foil drip pan in center of grate between coals. position cooking grid with handles over coals so briquets may be added as needed.
place roast on grid directly over one side of medium, ash-covered coals, sear, uncovered, 5 minutes or until bottom of roast is browned. turn roast over and place in center of grid directly over drip pan. grill, covered, 35-45 minutes for medium rare, 45-60 minutes for medium doneness, turning occasionally. (add 3-4briquets per side every 30 minutes to maintain heat level.).
remove roast when internal temp is 135 degrees for med rare, 150 for medium. transfer to carving board and tent loosly with tinfoil. let sit 10 -15 minutes. carve and enjoy!