Over medium high heat, add onions and fry for 1 minute. Add in garlic and ginger and fry for another minute. Add in the mushrooms, carrots, potatoes and soy curls, and cook for 5 minutes.
Add vegetable broth or water and grated apple. Bring to a boil and then reduce heat to a low and simmer for 15 minutes or until you can pierce a toothpick through it.
Turn off the heat. Chop up the roux into small pieces (makes it easier to dissolve). Add the chopped roux to a soup ladle and dissolve it well into the curry. Stir in kakushi aji mixture. Add any other kakushiaji.
Turn heat to low and simmer to thicken, about 5 minutes.
Serve over rice and enjoy!
Thinly slice the onions (*previously, I have diced the onions, but have since kept them just thinly sliced).
Heat butter in a medium pan over medium heat until melted. Stir the onions until softened and become translucent.
Reduce heat to medium low and continue to cook, stirring every few minutes to prevent them from sticking and burning until light amber (about 20 minutes). Continue to caramelize until golden brown. If at any point it looks like the pan is burning, add a splash of water to deglaze the pan.
You can stop here at the point where they are soft and jammy or continue to cook for another 10 minutes until slightly blackened around the edges.
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Customize your curry + Kakushi Aji
Straight out of the box, you have a good curry but adding other condiments and flavourings is the key for really delicious Japanese curry.
Both my grandma and mom would mix two different brands with different spice levels of curry roux for a more complex flavour (Torokeru & Golden Curry were our go-tos). Then they would add kakushi aji ingredients, which are ‘hidden flavours‘ that come from all kinds of condiments. The most common you’ll see Japanese people use are caramelized or fried onions, apples, ketchup and honey. In our household, we always added Worcestershire or Tonkatsu sauce! Here are more ingredients you can try adding (bolded are ones I always include):
Apples
Banana
Ketchup
Worcestershire sauce
Tonkatsu sauce
Soy sauce
Coffee
Chocolate
Cocoa powder
Mirin
Caramelized onions (store bought or homemade)*
Fried onions
Sake
Rice vinegar
White or red wine
Yogurt
