To make the crepes: Place a nonstick skillet on the stove over low heat. Add a little oil and let the pan get very hot. Remove the pan from the heat for about 30 seconds (if the pan is too hot, the crepe will have holes). Pour in a thin layer of batter (not too thick or it won't be crispy). Quickly add pork, shrimp, bean sprouts, and onion (press the pork and shrimp into the batter, then add the bean sprouts and onion on top). Cover and cook for about 2 minutes. Uncover, let the crepe crisp up a bit, then fold it in half (if you fold before it's crispy, the crepe will tear; if you wait too long, it may break).

Fry each side until slightly crispy and golden brown, then remove from the pan. After using up all the batter, to keep the crepes crispy, reheat them in an air fryer at 285°F (140°C) for 10 minutes before serving (add more time if needed for extra crispiness).