In a large bowl, combine ham, broccoli, onion, parsley, mustard and cheese. Stir well.
Unroll crescent roll dough, and arrange flat on a medium baking sheet. Pinch together perforations to form a single sheet of dough. Using a knife or scissors, cut 1 inch wide strips in towards the center, starting on the long sides. There should be a solid strip about 3 inches wide down the center, with the cut strips forming a fringe down each side. Spread the filling along the center strip. Fold the side strips over filling, alternating strips from each side. Pinch or twist to seal.
Bake in preheated oven for 20 to 25 minutes, until deep golden brown.
