Wash the prawns and pat it dry.
Mix together ginger-garlic paste, cumin powder, tamarind pulp, red chilly powder, salt and rice flour.
Blend 2 tbsp of oil into the above mixture.
Marinate the prawns in this mixture for at least 2 hrs, preferably in the refrigerator.
Heat oil in a pan.
Add marinated prawns and cook for a min on a high heat.
Turn over the prawns and cook for another min.
Reduce heat and cook for 2 - 3 mins., turning prawns occasionally for uniform cooking.
Remove, drain onto an absorbent kitchen towel or paper.
Sprinkle lemon juice.
:- Serve hot.