Prepare a cookie sheet with parchment paper
Lay pork sausages onto a baking tray drizzled with oil, rosemary, salt and pepper, and scattered with a few onion piece
Roll puff pastry out into a rectangle, then cut into 6 squares
Slather onion jam onto puff pastry squares
Lay the puff pastry squares over the top of the sausages, jam side down
Crimp the edges decoratively, cut a few slits for steam, then brush with egg wash
Bake in at 350F for 30 minutes, until golden brown
Flip the upside down hot dogs over
Dress with ketchup and mustard
