Directions

1. Preheat oven to 425 F.
2. Line 2 large baking sheets with foil.
3. In a large bowl, toss potatoes with oil, rosemary, black pepper and garlic powder.
4. Divide potatoes between sheets, spreading in an even layer. Season potatoes with salt, to taste.
5. Bake potatoes for 20 minutes, remove and flip the potatoes. Rotate the pans, returning to the oven and bake until golden brown and crisp, approximately 10-15 minutes. Remove from the oven and let cool for 5 minutes.
6. Take one pan of potatoes and move the potatoes toward the center of the baking sheet so they overlap slightly. Sprinkle half the bacon, half the corned beef, half the white cheddar and half the cheddar Jack cheese and half the red onion over the potatoes. Arrange the potatoes from the second sheet pan over the top and top with remaining bacon, corned beef, white cheddar, cheddar-jack and red onion.
7. Return the potato nachos to the oven and bake until the cheese melts, approximately 5 minutes.
8. In a small bowl, combine the sour cream and fresh horseradish. Top the nachos with the sour cream mixture and sprinkle the sliced jalapeños, and chives over the top.