03Remove potatoes from oven and let cool to a workable temperature. Slice potatoes in half, lengthwise and remove the flesh of the potato with a spoon to a bowl. Mix in butter, add pepper and salt to taste. Reserve 8 of the skin halves, discard the other 8.04Gently fold in the onion, jalapeno and garlic mixture into the potato. Combine the horseradish, sour cream, half the pepper jack cheese and the bacon; add to the potato mixture. Gently fold in the avocado.05Stuff the potatoes with mixture, top with the remaining cheese and place back in the oven on a baking sheet for 20 minutes at 350 degrees F.