Prepare the Chicken: Pat the cubed chicken breast dry with a paper towel. This helps it brown nicely. In a medium bowl, toss the chicken pieces with the 1 tablespoon of cornflour until they are lightly and evenly coated. Season with a pinch of salt and freshly ground black pepper.

Mix the Sauce: In a separate small bowl or jug, whisk together all the sauce ingredients: the soy sauce, mirin, sake, brown sugar, grated ginger, and minced garlic. Set this aside for now.

Sear the Chicken: Heat the sesame or vegetable oil in a large, non-stick frying pan over a medium-high heat. Once the oil is shimmering, carefully add the chicken pieces in a single layer. Be sure not to overcrowd the pan; cook in two batches if necessary.

Cook Until Golden: Fry the chicken for 5-7 minutes, turning the pieces occasionally, until they are golden brown on all sides and cooked through. What works best for me is to let them sit for a minute or two without moving to develop a good crust on one side before turning. For a guide on ensuring your chicken is perfectly cooked, check out this great article on how to cook chicken breast.

Start the Sauce: Once cooked, remove the chicken from the pan with a slotted spoon and set it aside on a plate. Reduce the heat to medium.

Simmer and Thicken: Pour the prepared teriyaki sauce mixture into the hot pan. Bring it to a gentle simmer, scraping up any browned bits from the bottom of the pan with a wooden spoon – this is where so much flavour is!

Reduce the Sauce: Let the sauce bubble gently for 3-4 minutes. It will start to thicken and become glossy as the sugar caramelises and the liquid reduces. You'll know it's ready when it coats the back of a spoon.

Combine and Coat: Return the cooked chicken to the pan. Stir everything together gently to coat each piece of chicken in the thickened, sticky sauce. Let it cook for another minute for the flavours to meld together.

Serve Immediately: Take the pan off the heat. Serve the chicken teriyaki immediately over steamed rice, garnished with a sprinkle of toasted sesame seeds and sliced spring onions.