Season the coconut milk with red chili flakes and minced garlic then stir well. Set aside.
Preheat a steamer over medium heat then prepare a disposable aluminum pan.
Combine the prawn with chopped tomatoes, lemon grasses, fresh basils, and grated coconut then stir well.
Place the mixture in the prepared aluminum pan then spread evenly.
Pour the coconut milk over the mixture then steam for approximately 15 minutes.
In the meantime, pour water into a pot then bring to boil.
Once it is boiled, stir in chopped spinach and season with sliced shallots. Stir well and remove from heat.
When the steamed prawn is done, remove from the steamer and transfer to a serving dish.
Serve with spinach soup.
Enjoy.