Rub the potatoes with some olive oil and sprinkle with salt and pepper. Put the potatoes on a foil-lined baking sheet and bake until the insides are soft and the outsides are crisp, 1 hour to 1 hour 30 minutes (the baking time will depend on the size of your potatoes).
Carefully split the potatoes lengthwise and scoop out the contents into the bowl of a stand mixer (reserve the potato skins on the baking sheet). Add the blue cheese, hot sauce, cream cheese, jalapenos and some salt and pepper to the mixer bowl and mix until combined using the paddle attachment.
Spoon the mixture into the potato skins, then top with the Cheddar. Bake until the contents are warmed through and the Cheddar is melted, 15 to 20 minutes.
Drizzle the potatoes with the ranch dressing and top with the chopped chives. Serve warm.