Food; how to make Japanese curry

I made Japanese curry for my close and good American friends yesterday. I wanted them to eat Japanese food made by real Japanese. First, we went to Wal-Wart to buy ingredients. We need potatoes, onions, calottes, beef, and curry roux. You can put in chicken instead of beef. Ingredients are very simple and you can make it easily. After shopping, prepare one pot, pour water into half of the pot and heat it. Next, peel potatoes, onions, and calottes. You can put and boil beef first in the hot water while you are peeling. Finishing peeling vegetables, you put potatoes first, because it takes longer till they are tender. Then you can put other vegetables at the same pot. You can let it look for about 10 minutes to make them tender. After that you take the curry roux and melt it in the same pot. Even if you melt all the curry roux, you have to keep heating and mixing ingredients and curry roux. When the roux is pulpy, you can finish heating and pour the curry roux in on the rice on your dish.