In a large frying pan, melt ghee on medium-high heat (or heat oil for 1 minute). Add cumin seeds and allow them to sizzle for 30 seconds. Add onions and sauté 5 to 8 minutes, or until dark brown but not burned. Stir in tomatoes, coconut milk, vinegar, chilies and the remaining 1 tsp of salt. Cook for 5 minutes, or until tomatoes are cooked through. Add green onions and stir well. Add prawns, stirring constantly until they become pinkish-orange. This will take about 3 minutes. Immediately remove from the heat.

To serve:
Place 5 prawns on each of six small shallow plates. Top each serving with one-sixth of the coconut masala. Alternatively, divide the coconut masala evenly among six small shallow plates, then top with 5 prawns per plate.

wine:
A Pouilly-Fume or Sancerre wine is a great sipping wine with this masala.