Preheat the oven to 400 degrees F. Line a rimmed baking sheet with parchment paper. Pierce the potatoes in several spots with a fork and place the potatoes on the prepared baking sheet. Place in heated oven for 1 hour. Remove and allow to cool slightly on the baking sheet. Reduce the oven temperature to 350 degrees F. While the potatoes cool, make the taco meat.
In a large skillet, heat the olive oil on medium-high heat. Add the onion, garlic and jalapeno to the skillet and sauté until the onion begins to turn translucent (about 3-4 minutes).
Add the ground beef and brown until no pink is showing. Add the spices (chili powder, cumin, smoked paprika, coriander, oregano, salt and cayenne pepper), tomato paste and chicken stock. Stir together and allow to simmer on medium-high heat until most of the liquid is absorbed/evaporated (about 5 minutes). Remove from heat.
Slice a very thin strip off the top of the potatoes. Gently hollow out the potatoes leaving at least 1/8-inch of the potato with the skin; put the insides of two of the potatoes in a large mixing bowl and set aside the insides of the remaining two potatoes for another use.
Using a potato masher or ricer (my preference), mash or process the potatoes. Add the sour cream, ¾ cup of the cheese and salt and pepper to taste. Mix together until all ingredients are well combined.
Add ¾ of the prepared taco meat to the bowl with the mashed potatoes and mix together.
Place the potatoes again on the parchment-lined baking sheet, spoon the meat-potato mixture evenly back into the potatoes. Divide the remaining taco meat and add on top of each filled potato. Top the taco meat with 1 tablespoon of the remaining cheese and place back into the oven to cook until warmed through (20-25 minutes). Serve hot with a choice of toppings.