Pigs in blankets—hot dogs baked in squares of buttery, flaky pastry—are things we think of making for the kids, then end up scarfing ourselves. In other words, their appeal is ageless. Maybe, when you were small, your mom used canned biscuit dough. All-butter frozen puff pastry is even better, baking up light and remarkably delicate—not a word that usually springs to mind in discussions of pigs in blankets. Serve these still slightly warm, with something nice for dipping: Fig Mustard, Sweet Hot Mustard, or (for the little ones) Honey Mustard.
Place a mini hot dog on the other end, and roll to enclose it; transfer to a baking sheet. 
Repeat with the remaining hot dogs and pastry, arranging them on the baking sheets in a single layer, without touching. 
Brush the tops with the remaining egg wash and sprinkle with seeds, if using. Transfer to the refrigerator and chill for 15 minutes. 
