Combine oil, honey, chilli powder, garlic and hot sauce in a bowl; whisk together. Place chicken breasts in a large resealable freezer bag; pour in marinade and seal bag. Marinate chicken in fridge for 3 hours.
Preheat oven to 230 C / Gas 8.
Place sweet potatoes in a roasting tin. Place mini corn on the cobs in a shallow baking tray. Brush with oil; season with salt and pepper and cover with foil.
Bake in the preheated oven until corn is roasted and brown, about 25 minutes. Continue baking until sweet potatoes are tender, about 45 minutes more.
Allow corn and sweet potatoes to cool until easy to handle, about 20 minutes. Cut kernels from cobs of corn; transfer half to a blender. Peel and cube sweet potatoes; add to the blender. Add cream; puree. Transfer mash to a bowl; stir in the remaining corn. Season with salt and pepper. Cover and keep warm.
Preheat barbecue for medium heat and lightly oil the grilling grate.
Remove chicken from bag and place on preheated barbecue grate; discard remaining marinade. Cook chicken breasts until juices run clear, about 6 minutes per side.
Slice each chicken breasts into 3 equal pieces; serve on top of sweet potato and sweetcorn mash.