Place 12 wooden skewers into a large roasting tray of cold water to soak – this will stop them from burning. Peel the garlic and ginger, then finely grate and place into a large mixing bowl. Add the yoghurt, passata, 1 tablespoon of oil and the spices, then mix well. Slice the chicken into bite-sized chunks and add to the bowl, then season with a tiny pinch of sea salt. Toss everything together to coat, then cover with clingfilm and place in the fridge to marinate for around 2 hours. Meanwhile, halve and deseed the pepper, then roughly chop into chunks, roughly the same size as the chicken. Remove the skewers from the tray, discard the water and wipe the tray dry. Divide and thread the ingredients between your skewers – don’t push them too close together otherwise they won’t cook properly, then place onto the tray. Put the griddle pan on a high heat to warm up (or you could cook them under the grill or on the barbecue). Drizzle the skewers with a little oil, then place onto griddle and cook for 10 to 15 minutes, or until cooked through, turning every 2 minutes to get nice and golden on all sides – you may need to work in batches. Once cooked, transfer the kebabs to a platter and serve with a fresh zingy salad and some rice or flatbreads.