Marinate the chicken pieces in the yogurt, lemon and cinnamon for about an hour. Soak the saffron threads in the chicken stock.
Over medium heat, in a large pan with a lid, melt the butter along with 1 tablespoon oil and add the rice, stirring it to coat until glossy. Pour in the saffron and chicken stock, add the cardamom pods, lemon juice and zest and bring the pan to the boil, then clamp on a lid and turn the heat down to very low. Cook like this for about 10-15 minutes, by which time the rice should have absorbed the liquid and be cooked through.
While the rice is cooking, shake the excess yogurt marinade off the chicken using a sieve. Then fry the meat in a hot pan with the remaining spoonful or so of oil, and do this in batches so that the chicken colours rather than just pallidly stews to cookedness.
When the rice is cooked, take it off the heat and fork through the pan-bronzed chicken pieces. Toast all the nuts except the pistachios, by simply shaking them in an oil-less frying-pan over a medium heat until they colour and begin to give off their waxy scent, and then add them to the pilaf along with the chopped parsley. Pile everything on to a plate and add a fabulously green sprinkling of slivered or roughly chopped pistachios.