01 - Heat 1 tablespoon oil in a large skillet over medium-high heat. Add diced potatoes and season with salt, pepper, and garlic powder. Cook stirring frequently until golden and crisp, approximately 12–15 minutes. Remove from skillet and set aside.
02 - Combine shredded cabbage, grated carrot, green onions, parsley, mayonnaise, Dijon mustard, apple cider vinegar, salt, and pepper in a mixing bowl. Toss thoroughly until all vegetables are evenly coated. Set aside to allow flavors to meld.
03 - Heat remaining 1 tablespoon oil in the same skillet. Add shredded corned beef and sauté for 2–3 minutes until heated through and slightly crisped at edges.
04 - Heat tortillas in a dry skillet for 30 seconds per side or warm in microwave until soft and pliable. Keep warm until ready to assemble.
05 - Place a layer of crispy potatoes on each warm tortilla. Top with warmed corned beef followed by a generous spoonful of cabbage slaw. Finish with a drizzle of sour cream across the top.
06 - Serve tacos immediately while tortillas are warm and potatoes remain crisp. Offer extra slaw on the side for guests who prefer additional crunch.