Japanese curry roux
A rich, mildly spiced homemade Japanese curry sauce with apple and tamari, made gluten free and vegan.
Make this once, then cook it into 17 different dishes.
- Time45 min
- LevelEasy
- Costabout £4.10 a head
- Makesabout 1.1 litres, enough for 2 or 3 curries for 4 people
Cost is worked out from Aldi and Tesco shelf prices in October 2026. Your shop and brands will differ.
Ingredients
Tick what you need to buy. It goes on your shopping list.
Method
- 1
Heat the oil in a large, heavy saucepan over a low to medium heat. Add the flour and stir constantly for 6 to 8 minutes until the roux turns a deep golden brown and smells nutty.
7 min - 2
Stir in the curry powder and garam masala and cook for 1 minute, until fragrant. Take care not to burn the spices.
1 min - 3
Add the onion, apple, garlic and ginger and cook for 5 minutes, stirring, until the onion has softened. Stir in the tomato purée and cook for 1 minute.
5 min - 4
Add the stock a splash at a time, whisking well between additions so there are no lumps. Bring to a simmer.
- 5
Simmer gently for 20 minutes, stirring now and then, until the sauce is thick enough to coat the back of a spoon.
20 min - 6
Stir in the tamari, maple syrup and ketchup. Taste and add a pinch of salt if needed. For a smooth sauce, blend with a stick blender.
- 7
Cool in shallow containers within 90 minutes. You should have about 1.1 litres.
About japanese curry roux
Japanese curry roux is a thick, mildly spiced brown curry sauce made by cooking flour and oil into a roux, then adding curry powder, aromatics and stock. It is the sauce behind Japanese katsu curry, curry rice (kare raisu) and curry udon.
It tastes savoury, gently sweet and warmly spiced rather than fiery, with a velvety texture from the roux and a rounded sweetness from grated apple and a little tomato. Most people in Japan make it from boxed roux blocks, but a homemade sauce is just as easy, and you control the ingredients.
This version is gluten free, dairy free and vegan, using gluten free flour, tamari and vegetable stock. One batch makes about 1.1 litres, enough for two or three curries for four people at 400 ml each.
Tips
- Cook the roux until it is deep golden brown. A pale roux tastes of raw flour, and a very dark one tastes bitter.
- Add the stock slowly and whisk well. Gluten free flour can clump if the liquid goes in too quickly.
- The sauce thickens as it cools, especially with gluten free flour. Loosen with a splash of water or stock when reheating.
- Grated apple gives the characteristic mild sweetness. A spoonful of honey or a small grated carrot also works.
- Add a square of dark chocolate or a spoon of instant coffee for the deeper, darker flavour of boxed roux.
Storing and freezing
Cool within 90 minutes and keep in the fridge for up to 4 days, or freeze in 400 ml portions for up to 3 months. Reheat until steaming hot all the way through, stirring often, and loosen with a splash of water.
Dishes you can make with japanese curry roux
Tofu Katsu Curry with Gluten Free Panko
DFNFVEbi Katsu Curry (Crumbed Prawn Curry)
GFDFNFGyu Kare (Slow Cooked Japanese Beef Curry)
GFDFEFKaisen Kare (Japanese Seafood Curry)
GFDFEFOmu Kare (Curry Omelette Rice)
GFDFNFYaki Curry (Baked Cheesy Curry Rice with Egg)
NFSapporo Soup Curry (Supu Kare) with Chicken
GFDFEFKare Ramen (Japanese Curry Ramen)
DFNFKare Pan (Japanese Curry Bread Buns)
DFNFDry Keema Kare (Japanese Dry Curry with Beef Mince)
GFDFEFKare Spaghetti (Japanese Curry Pasta with Chicken and Mushrooms)
DFEFNFNatsuyasai Kare (Japanese Summer Vegetable Curry)
GFDFEFQuestions
Is this Japanese curry sauce gluten free?
Yes. It uses gluten free plain flour, gluten free curry powder, tamari and vegetable stock. It is also dairy free, egg free, nut free and vegan. Always check the labels of the stock, curry powder and tamari.
How spicy is Japanese curry?
Mild by design. It is warmly spiced and slightly sweet rather than hot. For more heat, stir in a pinch of cayenne or chilli flakes at the end, or serve with a little chilli oil or sambal.
Can I use ordinary flour?
Yes, if you are not avoiding gluten. Use the same weight of plain flour. The sauce will be smoother and a touch thicker. The recipe is no longer gluten free.
What can I serve it with?
Katsu chicken or tofu, boiled potatoes and carrots, rice, udon noodles or fried aubergine. Add pickles such as pickled ginger or fukujinzuke on the side.
Can I make it ahead?
Yes. The flavour improves after a day in the fridge. Make it up to 4 days ahead, then reheat gently with a splash of water, stirring until hot all the way through.
More base recipes
Double check before you cook. Recipes can contain mistakes. Any diet labels come from the ingredients as written in this recipe and are a guide, not a guarantee. Always check every ingredient and the packet label for allergens and cross contamination, and ask your doctor or dietitian what is right for you, especially with coeliac disease, diabetes or a serious allergy. This is not medical advice.