I normally will stir fry my prawns with a bit of oil first so that when you finally cook them your sambal won't be watery.
All you need for a result like above are:-
2 big onions cut into rings.
4 garlics sliced into strips.
3 tablespoons of cili boh(if you are a cili queen then add more:)
2 tablespoon tomato ketchup
salt/sugar to taste.
Fry 3 tablespoon of oil and stir fry the onions and garlic.
Add in the cili and fry till fragrant before adding the ketchup.
Stir in the fried prawns.
Salt and sugar to taste.
This is my