Kill and clean crab and pull legs off body. Lay crab pieces including body on paper towels and cover with plastic wrap or kitchen towel. Use mallet or hammer to crack legs and body. In a large glass 9x13 dish assemble crab pieces. Sprinkle 1 tbs. Back of the Yards Garlic Pepper Butcher's Rub over crab. Slice butter into thin pats and lay over crab, do this until the entire stick is used. Sprinkle the remaining rub over the crab and butter. Cover with foil and cook at 350 degrees for 20 minutes. Uncover and roast for an additional 10 minutes.