Optional step: If your 450 g beef steaks are lean, sprinkle all over with salt and place on a wire rack over a container. Refrigerate uncovered to dry brine it. I suggest skipping this step if you use marbled wagyu.
Pour ½ tbsp cooking oil into a large cold pan. Thinly slice 2 cloves garlic and place them in the oil. Heat on low and cook until the garlic is golden all over.
As each piece of garlic crisps up, lift it out of the pan and place it on a piece of kitchen paper. Be careful not to let the garlic turn dark or burn.
Blot the surface of the beef steak with kitchen paper so that no surface moisture remains. Once all of the garlic is out of the pan, increase the heat to high and place the steak inside. Flip it every 30 seconds for about 4 minutes, 8 times in total. This timing is based on a 2-3cm thick steak, adjust according to the thickness.
Transfer the seared steak to a wire rack over a container to catch the drips.
Reduce the heat to medium, and deglaze the pan with 1½ tbsp red wine and 1½ tbsp mirin. Add 1 tsp sugar and any beef juices accumulated in the container. Mix well with a spatula, scraping the bottom of the pan as you go.
After the sauce has been bubbling for about 1 minute, turn off the heat and pour 1½ tbsp Japanese soy sauce (koikuchi shoyu) down the edge into the pan. Mix well, then stir in 1 tbsp unsalted butter until glossy.
Slice the beef into strips against the grain.
Divide 2 portions cooked Japanese short-grain rice into serving boxes and brush with half of the sauce.
Fan the sliced beef through the center of the rice and top with finely chopped green onions and the crispy garlic chips from earlier. Sprinkle with ground black pepper and serve with a blob of wasabi paste. Enjoy!
Notes
Keep the rice plain: Hot short-grain rice with nothing stirred through it, no vinegar, no salt, no oil. It is there to soak up the tare and the rendered fat, and seasoning it sends the whole bowl in a different direction.Match the dry brine to the cut: Salt lean, meaty beef steak a day ahead for real gain. On finely marbled wagyu ribeye I'd skip it, since I prefer the texture when I leave the salt off and season at the pan. A personal preference, not a rule.Blot the steak bone dry before searing: A wet surface steams instead of browning, so no crust forms. Pat both sides with paper towel right before the pan, whether or not you dry brined it.Add the soy and butter off the heat: Kill the heat before the soy goes in down the side of the pan, then swirl in the butter. Cooking this sauce down turns it sticky and oversalted.