Soak and par-cook: Place potato wedges in cold water for 20 minutes to remove excess starch, then pat dry. Boil in salted water for 5 minutes until just tender - you want a slight give, not falling apart.
Dry and dust: Drain thoroughly and dry on a wire rack for 10 minutes. Toss with cornflour and a pinch of salt until evenly coated; the cornflour yields the signature crackle.
Fry or air-fry crisp: Heat oil to 180 C / 350 F. Fry wedges in batches until golden and deeply crisp, about 6-8 minutes per batch, or air-fry at 200 C / 400 F for 20 minutes, flipping halfway.
Rest to retain crunch: Transfer cooked wedges to a wire rack so steam escapes. This keeps the exterior from softening and preserves textural contrast.
Make the glaze: In a skillet over medium heat, warm oil and sauté garlic until fragrant, about 20 seconds. Add honey, soy sauce, rice vinegar and ketchup. Stir until glossy and thickened - about 2 minutes; you’ll smell caramel notes and tangy steam.
Finish with chilli: Add chilli flakes or sliced fresh chilli and toasted sesame seeds to the sauce. Toss off heat once the sauce clings to the spoon with a syrupy ribbon.
Toss and serve hot: Place crisp wedges back in the skillet, toss gently until each piece is lightly glazed. Serve immediately so the contrast between crunchy shell and sticky glaze is at its peak.