Step 1: 1. Boil the potatoes in their skins in a large saucepan, over a high heat for 20- 25 minutes until they are tender. Drain well and cool slightly.
Step 3: 2. When the potatoes are cool enough to handle, peel them and cut them into bite sized cubes.
Step 5: 3. Fry the bacon gently in its own fat until crisp; remove from the pan and drain thoroughly on kitchen paper towels.
Step 7: 4. Add the onion to the bacon fat in the pan and fry gently for about 5 minutes or until they begin to turn golden.
Step 9: 5. Stir in the flour and the sugar. Add salt and pepper to taste.
Step 11: 6. Gradually blend in the water and the vinegar; bring to the oil and cook for about 2 minutes, stirring constantly until the sauce thickens.
Step 13: 7. Add the potatoes and bacon back to the pan. Mix gently and heat for about 10 minutes, stirring occasionally. Garnish with parsley.