Heat the oil in a large saucepan, one that owns a lid, and drop in the scallions. Cook, stirring for a minute or 2, and then add the curry paste.
Add the chicken pieces and keep turning over heat for 2 minutes, before adding the coconut milk, stock (or rather water and stock concentrate or cube) and fish sauce and then the frozen peas and soya beans.
Simmer for 10 minutes then add the frozen fine beans and cook for another 3 to 5 minutes.
Serve with rice or noodles, as wished, sprinkling over the coriander/cilantro as you do so. Put out a plate of lime wedges for people to squeeze over as they eat.