Peel the sweet potatoes and cut into chunks about 4cm square
Place in a pan of boiling water with the lemon juice and a little salt and simmer for 8-10 minutes until cooked but not soft
Mix together the flour, cayenne pepper and a pinch of salt
Drain the potatoes and then dust with the seasoned flour, coating the pieces well
Heat 15ml of the oil in a large frying pan and fry the onion for about 2 minutes
Add the bacon and fry over a gentle heat for 6-8 minutes until the onion and bacon are golden
Transfer to a plate using a slotted spoon
Add the breadcrumbs and fry, stirring, for about 1-2 minutes until golden
Add to the plate with the bacon
Heat the remaining oil in the pan and fry the potatoes for 5-6 minutes, turning occasionally, until evenly browned
Stir in the breadcrumbs and bacon mixture and cook for 1 minute
Serve at once