Put the potatoes and eggs
into a big saucepan
of cold salted water. Bring to a simmer
. After 12 minutes remove the eggs with a slotted spoon and let cool. Continue cooking the potatoes until a paring knife poked into them goes in without resistance, about 3 minutes longer. Drain
the potatoes in a colander and let them cool.
Reserve some scallion greens
. Meanwhile, stir together the mayonnaise
, mustard, pickles and their juice, onion
, remaining scallions
and capers, parsley, and lemon juice
in a bowl large enough to hold the potatoes. Peel
the cool eggs and grate
them into the bowl. Stick a fork into the potatoes and lift them 1 at a time out of the colander
. Break up the potatoes by hand into rough chunks, add them to the bowl and toss to coat with the dressing
. Season, to taste, with salt and pepper. Drizzle
with a little olive oil before serving.