What is most popular menu in Japan ? I think it is curry and rice. Adults and children love it so much. If Indians eat Japanese original curry, they will say it is not real curry. Certainly we can eat curry in Indian restaurant in Japan. However, it is different with curry that is made in our house. Real Indian curry is smoother and they eat it with Indian food, "Naan" like a baked pie sheet. The taste is spicier than Japanese curry. I love Indian curry, too.
We, Japanese eat with rice. Japanese curry sauce is more thickened and is put on rice. And Japanese pickles, "Rakkyo" or "Fukujin zuke" is essential item. And we distinguish the taste, sweet (Amakuchi), middle of hot (Chu kara), and very hot (karakuchi).
It is easy to cook it in our house. We can buy the solid cubic curry sauce in shopping store. We fry and boil a lot of vegetables. Main vegetables are carrot, potato and onion. Almost Japanese people put in meats or marine products in the curry. After all ingredients are boiled , we just put some solid cubic curry sauce into the pot. After waiting for 30 - 60 minutes sometimes stirring the curry sauce. It is ready to eat .
Curry Rice is so convenient and helpful menu for mothers. We can cook big volume of curry and eat for a few days. Curry rice is best food for family.
Moreover, there is more convenient way to eat it. It is an instant food like dry noodles. Curry sauce for one person is put in a tinfoil bag. It is OK to put the bag in hot water for 5 minutes. We are only ready for one cup of the rice and can eat delicious curry anytime. (The attached picture is instant curry of Nakamura-ya, that is long-standing and famous curry restaurant in Shinjuku.) But homemade curry is best.
I recommend you try to eat Japanese curry one time. You will definitely like it.