Heat the oil in a large skillet over medium heat. Add the corn, scallions, red pepper flakes and 1/2 teaspoon salt and cook until softened, about 5 minutes. Add the coconut milk and 1/2 cup water and simmer until thickened, about 5 minutes. Remove from the heat and stir in the cilantro and vinegar. Transfer to a serving bowl and sprinkle with cilantro.