How to Make It
In a large nonstick skillet, heat oil over medium-high heat. Add garlic, ginger, serrano chile and ground pork and cook, stirring occasionally, until pork is browned and cooked through, about 5 minutes.
Add cucumber, fish sauce and vinegar to skillet, then season with salt and pepper. Cook, stirring, until liquid is almost evaporated, about 2 minutes. Stir in cilantro. Serve pork mixture in lettuce leaves with lime wedges, if desired.