Light a barbecue and wait until the coals are ashen, set a gas barbecue to medium or heat a griddle pan over a medium-high heat. To prepare the salsa, cook the pineapple, onion halves and the chilli for 5-10 mins, turning, until charred. Remove everything to a board and leave to cool, then chop the pineapple and veg (you can roughly or finely chop, depending on your preference). Tip into a bowl, season with salt, then stir in the lime juice and coriander. Set aside.

Grill or griddle the frankfurters for 10-15 mins, turning until there are char marks on all sides and they begin to blister and sizzle. If you have space on the grill or in the griddle pan, toast the cut side of the buns at the same time. If not, do this after the frankfurters are cooked, but watch the buns carefully as they will be toasted in less than a minute.

Serve the pineapple salsa in a bowl alongside the frankfurters, buns and sriracha and let everyone build their own dogs. Alternatively, stuff the buns with the frankfurters, spoon over the salsa and drizzle with the sriracha.