Scrub the skin of the sweet potatoes clean, lightly poke the skin with a fork and wrap them in tin foil. Bake on the grill at high indirect heat for about 30-35 minutes, depending on the size of the sweet potatoes.
Add BBQ sauce to the chicken breast and season with salt and pepper. Barbecue for 6-7 minutes on each side and leave them to rest for 5 minutes. Shred the chicken breasts using two forks.
Slice open the sweet potatoes and top with shredded chicken. Add crème fraiche and grated Castello Tickler Extra Mature Cheddar. If you want the cheese to melt, just put the loaded sweet potato on the grill with the lid on for 2-3 minutes. Finish with spring onion and BBQ- or hot sauce.