Before you start, roughly cube 1 bell pepper, thinly slice 4 button mushrooms and ½ yellow onions, and mince 1 clove garlic .
Place 200 g thinly sliced beef in a mixing bowl and sprinkle with 1 pinch salt and pepper and ½ tbsp all-purpose flour, toss until evenly coated.
Preheat a large pan over medium/medium-low heat and add 1 tsp cooking oil. Once heated, add the beef and the sliced mushrooms.
Sear the beef on both sides and sauté the mushrooms until browned, then transfer to a heatproof container.
In the same pan, add the sliced onions with a pinch of salt. Cook until golden and soft. If they start to stick, add a splash of water and mix occasionally to unstick them.
Once softened, add the minced garlic and bell peppers. Fry for about 30 seconds or until fragrant.
Pour 4 tbsp red wine into the pan and increase the heat to medium/medium-high. Scrape the pan to deglaze and simmer until the alcohol aroma softens and the texture appears syrupy.
Add the beef and mushrooms back to the pan and sprinkle with ½ tbsp all-purpose flour. Mix until evenly distributed, then add 1½ tbsp tomato ketchup, 1½ tbsp Worcestershire sauce, and ½ tsp Japanese soy sauce (koikuchi shoyu). Stir fry for 1 minute.
Pour in 300 ml beef bouillon and add 1 bay leaf. Mix well and reduce the heat to a gentle simmer. Stir occasionally and simmer for about 5 minutes or until the sauce thickens and thinly coats the back of a spoon. While you wait, prepare the rice.
Heat a separate large pan or wok over medium and add 1 tsp butter and 1 clove garlic. Once fragrant, add 2 portions cooked Japanese short-grain rice (cooled) and stir fry for a few minutes to warm the rice through and evenly distribute the ingredients. Sprinkle with 1 tsp fresh parsley and then turn off the heat.
Once the hayashi is thickened, turn off the heat and add ½ tsp instant coffee powder, 1 pinch nutmeg powder and 1 tbsp unsalted butter. Mix until the butter has melted into the sauce.
Divide the rice between serving plates, then spoon the hayashi beef generously next to it. Finish with a pinch of parsley and enjoy!
Notes
Get thinly sliced beef: Look for sukiyaki/shabu-shabu packs or "shaved beef" (butcher can thin-slice chuck or sirloin). Slightly thicker slices are fine for a silkier bite.Swap protein if needed: Thinly sliced pork shoulder or pork belly works (milder, slightly sweeter) with the same method.Use a dry red (Merlot/Cabernet) and avoid sweet reds to keep acidity/tannin in balance.Adjust Worcestershire: British one is sharper/thinner than Japanese style, so use a little less. HP Sauce or a touch of A.1. can substitute.Use day-old, cold rice for cleaner separation; if freshly cooked, spread to steam off surface moisture before sautéing.Storage & meal prep: Chill fast and refrigerate hayashi (no rice) up to 3 days, freeze flat up to 1 month and keep rice separate (best frozen in portions). Reheat to 74℃ (165°F). Don't refreeze thawed portions.Serving ideas:Corn Potage, Japanese Potato Salad, Coffee Jelly, Purin.