Peel the potatoes and cut into half if they're very big. If the potatoes are small used them whole. Finely chop the onions.
Heat the pressure cooker, add oil and stir fry the ground meat, adding the onions a little later. Add the ○ ingredients and stir fry quickly. (Don't let the moisture evaporate!)
Put the potatoes on top of the ground meat, add 40 ml of water, and heat in the pressure cooker under pressure for 10 minutes. Leave to cool down and de-pressurize on its own.
Open the lid and evaporate the moisture in the pan over medium heat. (You can take out the potatoes before doing this if you prefer.)
Roughly mash the potatoes withe a spatula leaving lumps, and adjust the seasoning. Spread out in a shallow container to cool.
When the potato mixture has cooled down enough to handle, divide into 4 portions, and then let cool down completely
Form each portion into a patty and coat with cake flour, beaten egg and panko. If you shake off the excess flour and strain the beaten egg beforehand, the egg will coat the patties evenly.
Deep fry in 170 °C until golden brown. Done!
I've flavored the croquettes lightly, anticipating that most people will want to eat them with some sauce. If you prefer, increase the soy sauce and mirin to 2 tablespoons each.
Story Behind this Recipe
I wanted to eat croquettes flavored like the traditional Japanese dish of simmered potatoes.
When using a pressure cooker only a minimal amount of is added, so adjust the heat so that too much steam does not escape. The key to the dense, floury texture is to cook the potatoes whole! If you try to form and fry the croquettes while the potato mixture is still hot, or poke the croquettes, they may burst open.