1) In a pan with the boiling salted water, cook the potatoes for 15 minutes, or until just tender, drain well.
2) In a large skillet, thinly slice and brown the frankfurters in the oil, move aside.
3) Then stir in the onion and saute until soft.
4) Stir in the chopped peppers, salt, ground pepper and vinegar, then stir continuously and cook for about 2 minutes.
5) Add the drained potatoes into the skillet and toss gently to mix.
6) Spoon into a serving bowl and serve warm.