Preheat the oven to 200C/400F/Gas 6.
On a baking tray lay the pancetta flat and put into a hot oven for four minutes until crispy.
Drain on kitchen paper.
In a hot wok add the sesame oil and choi sum, and stir-fry for two minutes. Next add the soy sauce and then take off the heat.
Place the choi sum into a bowl and mix with the mango and coriander.
Serve on a plate and top with the crispy pancetta.