Place pork in a bowl along with spices and oil. Leave for a few mins if possible.
Pre-heat wok or frying pan and stir fry pork with onions for 5 minutes, turning in the pan to cook through.
Shred the lettuce and slice tomatoes finely.
When the pork is cooked lay each wrap on a flat surface, and scatter a layer of lettuce. Add a spoonful of pork, a few slices of tomato and a spoonful of fromage frais. Roll up and serve immediately.