Combine mango, coriander, mint, spring onion, lime juice, fish sauce, prawns and chilli in a bowl, toss to combine and set aside.
For coconut batter, combine rice flour and turmeric and salt in a bowl, then whisk in coconut milk and 350ml water. Set aside to rest (1 hour). Thin with a little water if necessary.
Heat 20 ml oil in a large frying pan over high heat, pour a ladleful of batter to make pancakes about 20cm in diameter.
Cook until golden (3-4 minutes), then flip carefully with a spatula and cook until golden (1-2 minutes), then slide onto a serving plate and keep warm.
Repeat with remaining oil, batter and filling, wiping pan with absorbent paper between batches.
Spread pancakes with a little chilli jam, top with mango prawn salad, scatter with shallots and peanuts and serve.