NOTE: When I don't have mirin in stock at home, I use "apple syrup". Dilute it five times with water.
1. Stab the pork with a fork, season the pork pieces with salt and pepper, then dust with flour. Now dip them in the beaten egg mixture. Finally coat with panko bread crumbs, evenly, pressing down gently. Both sides should be completely coated.
2. In a frying pan, heat up the cooking oil over medium-high heat until it reaches 180℃. Fry the pork until both sides are golden brown, turning them in the oil once or twice. Drain on a plate covered with paper towels.
3. Slice the cooked tonkatsu into strips. Set aside.
4.Making the dashi soup In a medium sized cooking pot, add water, soy sauce, cooking sake, brown sugar, dashi powder and mirin. Then add onion.
5. Heat it over medium-high heat and bring it to a boil, cook until the onion slices are translucent. Set aside.
6. In a small fry pan, pour a portion of the dashi soup from #5. Place one fried tonkatsu (sliced) in it and heat over medium-high. Pour beaten egg evenly, gently shake the fry pan to cook the egg mixture until desired consistency. Do not over cook. Cook only halfway!
7. Place the tonkatsu and the egg over the steamed rice gently.