Bring a large pot of salted water to a boil.
Add 6 potatoes and cook until tender but still firm, about 15 minutes.
Drain, cool, and chop the potatoes.
Place 4 large eggs in a saucepan and cover with cold water.
Bring water to a boil, cover, remove from heat, and let eggs stand in hot water for 10 to 12 minutes.
Remove eggs from hot water, cool, peel, and chop.
Place 450 grams of bacon in a large deep skillet.
Cook over medium-high heat until evenly brown.
Drain, crumble, and set aside the bacon. Reserve bacon drippings.
Place chopped potatoes in the skillet with reserved bacon drippings and fry until heated through.
Add chopped escarole, crumbled bacon, chopped eggs, and 1/4 cup apple cider vinegar to the skillet.
Cook until escarole becomes wilted and serve warm.