This is a Japanese classic dish that everybody loves, casual, home-style cooking. It reminds me of home, deli and casual dining where I used go to.When I miss Japanese food, this is one of my recipe that I would cook at home.
Boil potatoes in a sauce-pan with a good pinch of salt,medium to medium-high heat, for 12-15mintues or until potatoes are tender. Remove from heat. Drain well. Place the pan back onto a low heat, add potatoes back in; mash it by using potato masher. Remove from heat. Transfer it to a large bowl.Keep it aside to cool.
Once the potatoes are cooled down,add all the other ingredients and combine well.Keep refrigerated until you needed.
Serve with tomato wedges,some salad leaves whatever you like.