Heat oven to 450 degrees. Place potatoes in a pot filled with salted water, cover, and place over high heat. Bring to a boil and then turn heat down to maintain a simmer. Simmer potatoes until they are completely tender when pierced with a thin metal skewer, about 25-30 minutes. Take care not to break apart the potatoes when piercing. Drain potatoes.
Brush a large baking sheet with olive oil OR line one with a silicone baking mat. Place one warm potato on the sheet pan. Using a flat bottomed pot, bowl, measuring cup or a large glass, press down hard on the potato to flatten it, but not so hard as to break it completely apart. Repeat with all the potatoes on the baking sheet, making sure they are not touching. You may need a thin spatula to scrape the crushed potato off the bottom of your dish/glass as it can stick. If pieces break off, you can carefully push them back into the potato and they should re-adhere when baking.
Drizzle or brush the tops of each potato with olive oil and then salt and pepper each one. Place in the oven and bake until browned and they are crispy on the sides, 25-30 minutes. Remove from oven.
Using a spatula place the potatoes on the serving plate. Top each one with a dollop of sour cream and sprinkle with fresh chives.
Enjoy!