In a bowl take the chicken pieces, add salt and pepper, and mix. Add ¼ cup corn starch, and mix well to coat properly.
Prepare the sauce by mixing all the ingredients given under the sauce.
Heat a large heavy bottom pan and add cashews, roast them on medium-high flame for 5 minutes. Set aside, the cashews will turn crispy once cooled.
In the same pan heat 2 tablespoons of cooking oil on medium-high heat until smoking hot. Add the corn-starch-coated chicken pieces in a single layer in batches. Cook each side until golden brown.
Add roasted cashews and sauce, and toss until the sauce is well coated with the chicken. Cover and cook for 5 minutes on medium heat until the sauce thickens.
Garnish with spring onion, sesame seeds, and chili flakes (optional)
Serve hot with rice and steamed broccoli.