In a large bowl, mix together the peanut butter, soy sauce, lime juice and zest, garlic, root ginger, coriander and 4 tablespoons of water.  In a large non-stick wok or saucepan, fry the pork for approximately 3-4 minutes until browned.  Add the red pepper and spring onions and fry for a further 2-3 minutes. 

Serve the nutty stirfry on a pile of noodles or rice with extra stir fried vegetables.