Whisk the lime juice, chilli and oil together in a bowl. Season, add the prawns and leave to marinate for 10 mins.
Meanwhile, tip the grains into a sieve and pour over hot water from the kettle to slightly soften them. Drain well.
Divide the grains between two bowls. Top with the marinated prawns, avocado, radishes, mango and spring onions. Drizzle over any leftover marinade and serve the poke bowls with a sprinkle of sesame seeds, if you like.
