Start with your salad; in a saucepan, bring the vinegar, caster sugar and salt to a simmer. Remove from the heat and add the grated carrots to the boiling liquid.
Stir and set aside to pickle while cooling. In a second bowl, combine the mayonnaise with the tomato purée and add soy sauce and tabasco to taste.
Once the carrots are pickled and cooled, lift the carrots from the pickling liquid into a bowl. Add the cucumber, pickled jalapenos and coriander leaves and toss with a dash of fish sauce and soy sauce.
Set aside until ready to serve.
Preheat the barbecue to medium or until the charcoal ashes turn white. Place the sausages over indirect heat and cook for 8 minutes.
Switch to a high heat for the last few minutes to help colour the sausages. Once the sausages are cooked, warm the bread rolls and drizzle some mayonnaise or butter on the base.
Add the salad leaves, the sausages and then your Vietnamese salad.