Spray a deep-sided frying pan with oil spray and heat over medium-high. Add chicken and cook for 2-3 minutes on each side or until golden. Add coconut milk, stock, water, ginger and lime leaves, and bring to the boil. Reduce the heat to low. Cover and cook, turning chicken halfway through, for 30 minutes or until the chicken is just cooked through. Transfer the chicken to a chopping board.
Increase the pan heat to high and bring the coconut cooking liquid to the boil. Boil for 15 minutes or until reduced slightly (you should have about 3 cups of cooking liquid). Transfer to a heatproof jug.
Reduce the heat to medium and add onion, capsicum and red curry paste to the pan. Cook, stirring, for 3-4 minutes or until vegetables soften slightly. Add the reduced cooking liquid and sweet potato. Cook, stirring occasionally, for 15 minutes or until the sweet potato is tender.
Meanwhile, shred the chicken into large pieces. Place the mango in a food processor and process until smooth.
Add the chicken, mango puree and lime juice to the coconut mixture and bring to a gentle simmer. Cook, stirring, for 2-3 minutes or until heated through. Stir in spinach for 1-2 minutes or until just wilted. Serve with brown rice alongside.
