Combine the peppers and cream in a saucepan and bring the cream to a simmer over high heat. Reduce the heat to low and cook the peppers until tender, about 5 minutes. Transfer to a blender, add a three-finger pinch of salt, and purée—be sure to remove the center blender cap and cover the hole with a kitchen towel—until the contents are thoroughly puréed, about 2 minutes. Taste and add more salt, if needed.