Cut the watercress into 3cm pieces. Slice the avocado thinly (2–3mm) after removing the pit and peeling.

Halve the cream cheese pieces.

Trim excess fat and sinew from the chicken thigh, and make cuts in thicker parts to even out the thickness.

Heat salad oil in a pan over medium heat. Place the chicken skin-side down and cook for 3 minutes until browned. Flip, cover, and cook on low heat for 5 minutes until fully cooked. Add teriyaki sauce ingredients and simmer until thickened. Let cool and slice into 1.5cm strips.

Lay out two slices of bread on plastic wrap. Spread half the mustard on one slice, then layer lettuce, half the cream cheese, half the watercress, half the teriyaki chicken, half the avocado, and another lettuce leaf. Top with the second slice of bread and wrap tightly. Repeat for the second sandwich.