1/4 c  Onions, chopped very fine         3/4 ts Black pepper
    1/4 c  Celery, chopped very fine         3/4 ts Minced garlic
    1/4 c  Bell peppers, chopped fine        1/2 ts Dry mustard
      2 tb Unsalted butter                   1/2 ts Ground cayenne
      1 ts Salt                                4 lb Boneless sirloin roast
      1 ts White pepper                   
  In a small bowl combine the onions, celery, bell peppers, butter
  and seasonings, mix well.
  Place roast in a large roasing pan, fat side up.  With a large
  knife make 6 to 12 deep slits in the meat (to form pockets) down
  to a depth of about 1/2 inch from the bottom; do not cut all the
  way through.  Fill the pockets to their depths with the vegetable
  mixture, reserving about 1 tablespoon of the vegetables to rub
  over the top of the roast. Bake uncovered at 300F until a meat
  thermometer reads about 160F for medium doneness, about 3 hours.
  For rarer roast, cook until thermometer reads 140F. Serve immediately
  topped with some of the pan drippings if you like.
  From Paul Prudhomme's Louisiana Kitchen
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