Heat the oil in a medium saucepan and add the onion.
Cook over a low heat until caramelised, then add the garlic and ginger and cook for another minute or so until smelling aromatic.
Add the plain flour and curry flour and stir to coat the vegetables in the pan. Add the chicken stock, a dash at a time, until it's all incorporated with no lumps.
Add the carrots and simmer with the lid on until they're completely soft, stirring to make sure the sauce doesn't catch.
Allow the curry to cool before blending it until it's silky smooth, then pass it through a sieve. Add the coconut milk, double cream, honey, soy sauce. Set aside.
Meanwhile, bread and fry your chicken - dip the thighs in the plain flour, shake off excess, then into the egg and into the panko, making sure they are thoroughly coated.
Heat the oil to 170°C and shallow fry until crisp.
Brush the bread slices with kewpie mayo and sprinkle with sesame seeds on the outer sides. Sandwich the cabbage and a breaded chicken thigh and swiss cheese along with a good dollop of curry sauce, then gently griddle until molten, crisp and delicious.