Made in the traditional recipe without butter. Calf bones, beef gristle and potherb are added to sauce Espagnole and boiled well for a week, with the sauce filtered daily. This gives the finished sauce a smooth texture and a nostalgic and rich taste. The flavor of beef stew and "Hayashi rice" all depends on the sauce.
8 types of vegetable including bamboo shoots, onions, shiitake mushrooms and corn are boiled in bouillon with rice and are left to sit over night. This allows the flavor to penetrate deeply into the rice, and getting rid of the excess water improves the match with the tomato sauce, which you will surely understand if you compare it to so-called "Chicken rice".