Sprinkle the paprika over the chicken to season (I then put this into the fridge until ready to use).
Add the water to the curry paste and mix. Saut the onions in the butter and add the curry powder, cook off the spice for 2 mins over a med heat keeping a crunch in the onions.
Add the onion mix to the crock, add the chicken and pour over the sauce. Cook on low for 5 hours
If adding the extra onions and spice then do so 1/2 hour before serving.