Preheat oven to 400ºf. Cut the sheet of puff pastry in six equal squares of 6” x 6”. Brush the outer edges of each square of pastry with the egg wash. Brush the inside of each pastry square with the first measure of Dijon mustard. Place a sausage link on the bottom edge of each pastry square and roll up the pastry around the sausage. Seal the edges and bottom seam by pinching. Repeat with the remaining sausages. Place the pastry seam side down on a cookie sheet and bake in the oven for about 15 minutes or until golden, puffed, and until the sausage is hot throughout. Let cool for 10 minutes then slice each sausage into 6 bite size pieces with a serrated. If desired, serve with a dipping sauce made by whisking together in a bowl the whole grain mustard, second measure of Dijon mustard, honey and cider vinegar. Makes About 24 Hors D’Oeuvres.