How to Make It
Preheat oven to 400°F with rack 6 inches from heat.
Toss together plantain slices, oil, and kosher salt; spread in a single layer on a baking sheet. Roast at 400°F until plantains are lightly golden on bottom, about 15 minutes. Turn slices over, and continue roasting until evenly cooked and soft, about 15 minutes. Increase oven temperature to broil, and broil until deeply golden, 1 to 2 minutes. Sprinkle with flaked salt; serve warm.