Add the beef mince into a large mixing bowl along with the leek, breadcrumbs, sake, soy sauce, red miso paste and egg. Mix everything together with your hands until well combined.
500 g beef mince, ½ cup leek, 6 tbsp breadcrumbs, 4 tbsp sake, 1 tbsp soy sauce, 1 tbsp red miso paste, 1 egg
Form mixture into 6 equal size patties about 2 cm / 1 inch thick.
Heat the vegetable oil and sesame oil in a large frying pan over medium-high heat. Pop in your beef patties and cook for 4 – 5 minutes per side until cooked through.
1 tbsp vegetable oil, 1 tsp sesame oil
Optional: Lightly toast your burger buns in a toaster OR butter them and place butter side down in a large frying pan until lightly toasted. Transfer to serving plates ready to assemble.
6 bread rolls or burger buns
Stack a beef patty onto the base of a burger bun and slather (or artfully decorate) with your favourite ratios of Kewpie mayonnaise and Japanese BBQ sauce.
6 bread rolls or burger buns, kewpie mayonnaise, Japanese bbq sauce
Top with cabbage slices and the lid of your burger bun and serve immediately.
3 cabbage leaves