Green Potato Smørrebrød
In a medium saucepan, combine the apple cider vinegar with the sugar and 1 cup of water and bring to a boil. Add the pearl onions and a pinch of salt. Transfer to a heatproof jar and let cool completely. Refrigerate overnight. In a medium saucepan, cover the potatoes, lemon zest, dill stems and peppercorns