Once a staple of the diner industry -- including breakfast joints like IHOP and Waffle House -- a "pig-in-a-blanket" was a breakfast variation of the British dish known as "Toad in the Hole," pork sausages baked in Yorkshire Pudding batter. Most of us in the United States know the dish as a chubby little link sausage tucked into a soft buttermilk pancake.
There's also the appetizer version: tiny sausages baked in blanket of flaky phyllo pastry or the pigs-as-a-meal treat: an All-American hot dog wrapped in a sheath of packaged crescent roll dough and baked in a hot oven. And here's a low-fat version of this.
Back in the late 1980s, when I worked for a local pancake restaurant, I had customers who insisted that pigs-in-a-blanket were a classic hangover cure. I don't know about that, but in the wild and crazy and swinging '70s, I used to make them for my girl-about-town roommate who on more than one occasion would wake up -- horrified! -- on Saturday mornings with a pig in blanket sleeping next to her.