Step 1

To make the sauce, combine the sugar, tamarind puree, fish sauce, sriracha sauce and lime juice in a small bowl, and stir to dissolve the sugar. Set aside.

Step 2

In a wok or large skillet, heat the oil over high heat until almost smoking. Add the onion, capsicum and garlic and stir-fry until fragrant (about 30 seconds). Add the prawns and stir-fry for 1 minute, or until they have turned pinkish but are still translucent: you want them to be about half-cooked.

Step 3

Pour the sauce over the prawns and stir to coat. Let the sauce come to the boil, continuing to stir for 1-2 minutes. The sauce will reduce and thicken, cooking the prawns through.

Step 4

Spoon onto a deep plate, garnish with coriander, and serve immediately.