Boil the potatoes in their skin until tender, but not falling apart.
Meanwhile cook the bacon until it has given up almost all of its fat - crispy, but not overcooked. Mix the vinegar, olive oil, sugar and salt and pepper to make a dressing.
Drain the potatoes, peel if you wish, and slice them in 1/4 inch rounds. Place the greens in the bottom of the pot you used to cook the potatoes and place the potatoes on top of the greens. Add the bacon and then the dressing. Stir together.
Serve hot. You can rewarm the potato salad if needed.
Makes 4 servings.