Place the chillies in a bowl; pour enough water over them to cover. Allow the chillies to soak until softened; about 10 minutes; drain. Chop the chillies and set aside.
Grind the cumin, turmeric, coriander and mace using a mortar and pestle into a fine powder.
Add to the mortar the galangal, lemongrass, salt, onion, garlic, prawns paste, fresh turmeric and reconstituted chillies and grind into a paste.
Stir the fish sauce and palm sugar into the paste. Transfer to a large bowl.
Add the chicken to the paste and toss to coat the chicken evenly; allow to marinate for at least 20 minutes or up to 24 hours in the refrigerator.
Heat the oil in a large frypan over medium heat; cook the chicken until no longer pink in the centre and the juices run clear, 5 to 7 minutes.
Stir the water, 1/2 cup peanuts, ginger and tamarind juice into the chicken. Bring to a simmer and cook until thickened; 20 to 30 minutes. You can also cook this at a lower temperature for up to 2 hours. Garnish with 2 tablespoons peanuts to serve.