Boil or steam the cauliflower and place in a medium sized oven dish.
In a saucepan melt the butter over a medium heat.
For people making a white sauce base for the first time remove from the heat and gradually add the flour. For experienced cooks turn to a low heat and add the flour, continue to stir to prevent lumping.Add a little milk and keep stirring until all 600 ml is added. The slower you add the milk the less likely lumps will form.
Once browned add the yellow rice paste and pour in the white sauce.
Add half the cheese and pour over the cauliflower.
Sprinkle with cheese and cook in an oven for 20minutes or until golden brown.
Serve sprinkled with fresh coriander leaves and red chillies.