Prep the potatoes: Peel if you like, or leave skins on for texture. Cut into 1/4-inch sticks. Aim for even size for even cooking.

Soak for crispiness: Place cut fries in a large bowl of cold water for 20–30 minutes to remove excess starch. This helps them get crispy.

Dry thoroughly: Drain and pat the fries completely dry with clean towels. Moisture is the enemy of crisp.

Preheat the air fryer: Set to 380°F (193°C) for 5 minutes. A hot basket helps immediate sizzle.

Seasoning mix: In a small bowl, combine paprika, chili powder, garlic powder, onion powder, cayenne, sugar, 1/2 teaspoon salt, and black pepper.

Coat the fries: Toss fries with cornstarch first to lightly dust, then drizzle with oil and toss again until evenly coated. Sprinkle on the seasoning mix and toss to coat.

Air fry, first pass: Arrange fries in a single layer (a little overlap is fine). Cook at 380°F for 10 minutes, shaking the basket halfway through.

Air fry, finish: Increase to 400°F (204°C) and cook 5–8 more minutes, shaking once, until deeply golden and crisp. Thicker fries may need an extra 2–3 minutes.

Salt to taste: Immediately toss hot fries with the remaining 1/2 teaspoon salt or to taste. Hot fries hold seasoning best.

Make the cheese sauce: While fries cook, whisk evaporated milk and cornstarch in a small saucepan over medium heat until steaming. Lower heat, add cheddar and American cheese gradually, stirring until smooth. Stir in taco seasoning and hot sauce. If too thick, loosen with a splash of milk; if too thin, simmer 1–2 minutes more.

Serve: Pile fries on a plate, drizzle with warm nacho cheese, and add jalapeños or sour cream if you like. Serve extra sauce on the side for dipping.