Heat a medium skillet with water over medium heat. Add vinegar.

When water begins to simmer, add eggs, gently and toward the side of the pan. 

Swirl the water very gently to coax the white over the yolk. Cover and turn off the heat The eggs are finished when the white is solid but the yolk is still liquid, in 5 minutes. Transfer eggs to a shallow pan with warm water. The eggs can be held for hours.