Split open the cardamom pods and toast them with the cinnamon, star anise, coriander and cloves for about 2 minutes, stirring all the time so they do not burn.
Put spices in a spice bag, seal and set aside.
Char the spring onions, shallots and ginger (with their skin on) for about 5 minutes. Then peel and set them aside.
Fill a large stock pot with water and bring it to the boil.
Put the whole chicken in the boiling water and boil it for 7 minutes.
You will probably get some foam from the chicken floating on the surface.
Remove the chicken, discard the water and wipe the pot clean of the foam.
Return the stockpot to the heat and add in 3 litres of boiling water, the chicken and the prepared shallots, ginger and onions.
Bring back to the boil and then reduce heat to a simmer with the lid off.
After about 20 minutes remove the chicken, carve off the breasts, slice them and set these aside.
Return the rest of the chicken to the stock pot and simmer uncovered for a further 20 minutes.
Add the spice bag into the broth and simmer for another 20 minutes.
Sieve the broth and discard the vegetables, spices and chicken carcass.
Return broth to the pot and adjust seasoning. Add in fish sauce and sugar (if using) to taste. Then switch off the broth
Quickly blanch noodles and bean sprouts in boiling water to soften them.
Then layer food in the bowl in this order – bean sprouts, noodles, chicken breast and cover these with the broth.
Sprinkle over some black pepper and add toppings of your choice.