Place batter mixing bowl in the fridge with the flour, baking powder and salt. (Helps keep batter cold = crispier chicken)

Marinade: Mix Chicken and Marinade in a bowl. Refrigerate for 30 minutes.

Dust: Spread the 1/2 cup cornflour/cornstarch on a shallow plate. Scatter over about 8 to 10 chicken pieces, toss to coat, shake off excess, put on a plate. Repeat with all chicken.

Rack: Place a rack on a tray (for draining, Note 3)

Heat oil: Fill small pot or large saucepan with 4cm / 1.7" oil. Heat to 180°C/350°F on medium high stove (or until chicken starts sizzle straight away when dipped).

Make Cold Batter: Whisk together flour, cornflour/cornstarch, baking powder and salt. Pour in 7 tbsp soda water, then do minimum whisks just to combine (10 or so) - few lumps ok, better than whisking too much (changes coating texture).

Batter thickness: should fully coat chicken easily, not be see through, but not thick and heavy - see video at 44 seconds. Use extra water 1 teaspoon at a time to achieve right thickness.

Dredge: Drop 8 or so pieces of chicken into the batter. Turn to coat, then carefully place in oil.

Fry #1: Cook for 3 minutes until light golden and crispy - when you pick them up, you can tell it's very crispy.

Drain & repeat: Place on rack, repeat with remaining chicken - I cook in 4 batches, don't crowd the pot, brings oil temperature down too much.

Cool chicken for 20 minutes (Note 4). Meanwhile, make Sauce.

Place ingredients in a large saucepan over medium heat. Bring to simmer, then leave to simmer for 3 minutes.

Consistency should be like maple syrup (video at 1 min 11 sec). Turn off stove, place lid on to keep warm (when cool, gets too thick to toss chicken).

Heat oil to 200°C/390°F.

Add in half the chicken (you can crowd the pot for Fry #2). Cook for 90 seconds until it changes from pale golden to very golden (but not dark golden, chicken will overcook), then remove onto rack. More golden = crispier chicken.

Repeat with remaining chicken. (Feel the chicken - you can tell it's built-to-last crispy!)

Tumble into saucepan with sauce, use rubber spatula to quick toss until coated with sauce. (Sauce starts thickening if you take too long, so be quick!)

Pile chicken up over crispy noodles (if using), scatter with sesame seeds and green onion and serve!

At any point while oil is hot, drop wad of noodles into hot oil, wait 3 seconds until it puffs up, then remove with tongs.

Drain on paper towels, place on plate to top with chicken!