Combine the ingredients for the chicken marinade, apart from the chicken, in a blender with some salt and whizz until smooth.
Rub all over the chicken and marinate overnight.
For aji verde blend everything with salt to taste, and store in the fridge until needed.
When ready to cook, set up the barbecue for indirect cooking with the coals banked to one side. The coals should be hot embers with no flames. Set the temperature to 175°C, if using a barbecue with temperature control.
Oil the grill grates and brush off any excess marinade from the chicken thighs. Cook them over indirect heat (the side of the grill without the coals underneath) with the lid down for 45 minutes.
After 45 minutes, check the temperature. You can start serving the chicken when the internal temperature reaches 72°C. Return the chicken to the barbecue to cook for longer if necessary.
Serve with the aji verde.
