Make up 100ml chicken stock using ½ the chicken stock cube. Put all the marinade ingredients in a food processor and whizz until combined.
Put the pork racks in a large deep roasting tin. Pour the marinade over the ribs, cover with cling film and leave to marinate for 1 hour at room temperature.
Preheat the oven to 180°C, fan 160°C, gas 4. Remove the cling film from the ribs and cover the tin with foil. Bake in the oven for 50 minutes. Preheat the barbecue.
Remove the ribs from the oven. Brush with honey, remove from the tin and cook on the barbecue for 5-10 minutes each side, basting with the leftover marinade in the tin, until dark brown and cooked through.