Dust a rolling surface with flour and your rolling pin. Gently roll the puff pastry to be nearly double in size.
Cut your pastry sheet into 9 rectangles.
Cut your kielbasa in half, placing each long piece on the left side of the rectangle.
Brush your beaten egg on the exposed pastry and roll the kielbasa and pastry as you would a traditional pig in blanket. The egg creates a seal. Repeat with all rectangles.
Place in the refrigerator at least 30 minutes.
Meanwhile, preheat oven to 425.
remove from the refrigerator and brush the kielbasa with egg wash.
Place in the oven for 25-30 minutes or until golden brown.
Rest for 5 minutes and slice on a bias.