Japanese Curry is a highly popular dish both in Japan and Japanese restaurants all over the UK. Its mild spice taste makes this Japanese curry sauce a choice to suit everyones taste buds. S and B curry sauce can be used to cook-in or pour-over many things. This Japanese Curry Sauce is ideal for making Chicken Katsu Curry. S&B Mild Curry Roux is a mixture of wheat flour and butter or olive oil, which adds thickness to curry. Curry roux is a mixture of this roux with Japanese curry powder.