Make the pancake batter: combine flour and salt in a mixing bowl. Make a well in the centre, add the eggs and milk and whisk until smooth. Set aside while you make the filling.
Heat the oil in a wok or large frying pan. Brown the chicken, then add beansprouts, capsicum, ginger and garlic and stir fry 2 minutes.
In a small bowl combine the cornflour and soy sauce and mix well. Pour the mixture into the frying pan along with the pineapple and juice, vinegar and brown sugar. Stir well and bring to a simmer.
While the filling is simmering, make the pancakes. Brush a 20cm frying pan with oil and heat over medium heat. Add about 3 tablespoons batter to the pan and tilt to spread it out evenly. Cook 2 minutes then flip it over. Cook 30 more seconds and transfer to a warm plate. Repeat with remaining batter and stack the pancakes between layers of greaseproof paper.
When the filling is ready, use to fill each pancake. Fold the pancakes over and serve with a little more of the sauce drizzled on top.