Preheat the oven to 425°F.
In a large, heavy-bottomed pot, cover the potatoes with water and a generous amount of salt.
Bring to a boil, and cook until fork-tender, about 15–20 minutes.
Drain, and set aside to cool.
Gently crush the potatoes with the side of a knife, and place them in a 1.5-quart baking dish, pie plate, or other oven-safe vessel, layering with about three-quarters of the scallions as you go.
Pour the heavy cream over the potatoes, and season with salt and lots of cracked black pepper.
Drizzle with a bit of olive oil on the top before popping the dish into the oven.
Bake until the cream has caramelized a bit and bubbled up around the edges and everything is golden and crispy and creamy and delicious, 15–20 minutes.
Top with a bit of flaky salt, remaining scallions, and a scattering of herbs.
