Cut 2 pounds large russet potatoes into ¼–½ inch sticks. Soak in Ice water for soaking 30+ minutes.
Drain, rinse, dry completely with towels.
Mix all Cajun Sparkle ingredients 1 tablespoon kosher salt, ½ teaspoon black pepper, ½ teaspoon garlic powder, ½ teaspoon onion powder, ½ teaspoon dried rubbed sage, ¼ teaspoon smoked paprika, ¼ teaspoon MSG, ⅛ teaspoon cayenne pepper, ½ teaspoon dried oregano in a small bowl. Set aside.
Deep fry: Heat oil to 300°F. Fry in batches 4–5 min. Drain on wire rack, cool 10 min. Increase oil to 400°F. Fry again 2–3 min until golden and crispy.
Air fryer: Toss with 1 tbsp oil. Air fry at 350°F for 10–12 min, shaking halfway. Increase to 400°F, air fry 8–10 more min, shaking every 3 min.
Transfer immediately to a bowl. Season generously with Cajun Sparkle while hot. Toss to coat. Serve immediately.