Place chicken, turmeric and 1 tbs oil in a bowl and season with 1 tsp salt flakes and freshly ground black pepper. Toss to coat, then set aside for 30 minutes to marinate. For the spice paste, place all ingredients in a small food processor and whiz to a smooth paste. Set aside.
Heat remaining ⅓ cup (80ml) oil in a large heavy-based saucepan over medium-high heat.
Add the chicken and cook, turning halfway, for 4-5 minutes until golden brown. Transfer to a plate.
Reduce heat to medium-low and add spice paste. Cook, stirring, for 5-6 minutes until caramelised and fragrant. Return chicken to the pan, add potatoes and stir to combine. Add coconut milk, tamarind mixture, star anise and cinnamon and bring to a simmer. Reduce heat to low, cover with a lid, and simmer for 1 hour or until the chicken is tender. Season with sugar and lime juice.
Sprinkle with chilli and shallots. Serve with steamed rice and lime wedges.
