Thread the chicken pieces onto pre-soaked bamboo skewers, interspersing each piece of chicken with spring onion, pepper and mushroom.
Mix together the mirin, soy, rice wine and sugar and stir until the sugar dissolves.
Heat a griddle pan and brush the chicken with the glaze. Griddle turning every 30 seconds or so, brushing the top each time until the chicken is cooked through and the meat burnished a to mahogany glaze.