Stir the ground meat, green onions, soy sauce, ginger, sesame oil, garlic, cornstarch, and black pepper together in a medium bowl until evenly distributed. The mixture should look cohesive, with the aromatics spread throughout rather than gathered in pockets.

Portion heaping tablespoons of filling onto a plate, then cap each mound with a wrapper and press the dough against its top and sides while keeping the underside exposed. A snug fit helps the dough grip the tacky filling without needing a folded seam.

Heat the vegetable oil in a large nonstick skillet over medium-high heat, arrange the dumplings with gaps between them, and carefully pour the water around them with the lid ready before covering and steaming for 6 to 8 minutes, continuing as needed to reach the appropriate internal temperature below. The wrappers should soften from opaque and floury to glossy and slightly translucent, but their appearance alone cannot confirm that the meat is done.

Lift off the lid and keep cooking until the remaining water disappears and the exposed meat bases brown lightly. Listen for bubbling to give way to a sharper crackle, then check underneath for a golden crust.

Transfer the dumplings to a serving plate and finish with additional green onion and your chosen dumpling sauce. Serve while the tops remain tender and the freshly browned bottoms are crisp.