Place red chillies, birds eye red chillies, half the garlic, half the ginger, tamarind paste, 2 shallots and 1teaspoon fish sauce in a blender jar.
Finely chop half the lemongrass stalk and add to the jar. Add ½ teaspoon brown sugar and blendinto a smooth paste. Add salt if required.
Heat sesame oil and oil in a deep non-stick pan. Finely chop remaining shallots.
Add remaining garlic and ginger and sauté till light brown. Add chopped shallots and sauté for 1-2 minutes or till golden.
Slice the remaining lemon grass stalk and add alongwith the prepared paste, mix and sauté for 5-10 minutes.
Take rice in a bowl. Add ½ cup vegetable stock and 3-4 tablespoons orange juice. Cover with cling film and prick it with a knife. Cook in the microwave for 8-10 minutes or till well done.
Add ½ cup vegetable stock to the cooked sambal mixture and mix well.
Slice the onion and tomato. Roughly tear lettuce leaves and place these in a bowl.
Deseed avocado and cut into cubes. Put in the bowl.
Add remaining stock to the cooked paste mixture and mix well.
Add half the lemon juice, salt and Thai sweet chilli paste to the salad and toss well. Chill in the refrigerator.
To the cooked paste mixture, add the remaining fish stock, brown sugar and mix well. Add remaining lemon juice and prawns and mix well.
Chop celery and add half to the prawns and rest to the salad.
Add remaining orange juice, chopped coriander and salt to the rice and mix well. Heat in the microwave for 2 minutes.
Put the rice in a mould and transfer onto a serving plate. Place salad on one side. Add the sambal prawns over the rice.Garnish with parlsey sprig andserve hot.