Shred the cabbage finely using a sharp knife or a food processor.
Fry the cabbage in half of the butter in a large frying or wok pan on medium-high heat. It takes a while for the cabbage to soften, but don't let it turn brown.
Add spices and vinegar. Stir and fry for a couple of minutes more. Put the cabbage in a bowl.
Melt the rest of the butter in the same frying pan. Add garlic, chili flakes and ginger. Sauté for a few minutes.
Add ground meat and brown until the meat is thoroughly cooked and most of the juices have evaporated. Lower the heat a little.
Add scallions and cabbage to the meat. Stir until everything is hot. Salt and pepper to taste. Drizzle with sesame oil before serving.
Mix together the wasabi mayonnaise by starting with a small amount of wasabi and adding more until the flavor is just right. Serve the stir-fry warm with a dollop of wasabi mayonnaise on top.
