What makes these potatoes so unusual? Lemon juice.
Serves 6 • 12 medium-sized Yukon gold potatoes, scrubbed clean, unpeeled. (Yukons are a nice flavorful potato, good for boiling and smashing up--I find there's no reason to peel the potatoes but if you prefer to, go ahead)
• 2 shallots, finely minced (I mean this: finely minced. I don't cook the shallots in this dish because it adds a great crunchiness to the potatoes, but you don't want your guests getting a mouthful of raw shallot.) • a few glugs of olive oil
• 2 tablespoons mascarpone and/or butter • juice of one lemon
• salt and pepper
Cover potatoes with cold salted water, bring to a boil, reduce to a simmer, and cook until smashable (so you can stick a paring knife in it no problem), approximately 25 minutes.
I don't own a masher so I mix the rest of the ingredients into the steaming hot potatoes with a big fork. (If you have a masher, use it! It'll ward off potential potato burn.) Add the rest of the ingredients, taste for seasoning, and serve immediately.