Prep things: Finely slice the garlic, ginger and peppers. Soak your dried chillies in warm water while you go about your business. Cut the chicken thighs into cubes and place them into a large mixing bowl.
Add the marinade ingredients to the bowl with the chicken and mix with your hands until incorporated. Add the cornflour and a pinch of salt and pepper to the chicken, and mix until the chicken cubes are coated and separate. Add a touch more cornflour if this isn't happening.
Add the ingredients for the sauce into a bowl, mix, and transfer to a medium pot/saucepan. Bring to a boil and reduce to medium, with the aim of reducing by about half - you want a wooden spoon to leave a trail when you drag it through the sauce. Remove your chillies from the warm water.
Pour oil into a large pot and bring to a medium high heat. You want to deep fry the chicken, so how far up your pot/skillet you go with the oil will depend entirely on the size of it.
Add the chicken to the heated oil and fry until golden brown. Remove carefully and place onto kitchen towels to drain.
In a separate pan/wok, add 1 tbsp of oil and bring to a high heat. Add the ginger and garlic, along with the dried chillies and peppers, then add the sauce mixture. Bring the sauce to a boil and add the chicken, tossing to coat. Serve and enjoy.