Chicken Burgers with Tarragon Mayonnaise

1. Combine mince, onion, rind, sour cream and breadcrumbs in a large bowl and season. Using clean hands, mix well. Divide into 6 portions. Using damp hands, shape into patties. Put patties on a tray, cover and set aside

2. To make tarragon mayonnaise, put egg yolk, 2 teaspoons of vinegar and mustard in a small bowl. Whisk for 1 minute or until light and creamy. Add oil 1 teaspoon at a time, whisking constantly until mixture thickens. Increase flow of oil to a thin stream and continue whisking until it has all been incorporated. Stir in remaining vinegar and season well with salt and white pepper.

3. Preheat barbecue flat plate on medium-high until hot. Brush both sides of patties well with oil. Barbecue for 6-8 minutes each side, or until browned and cooked through.

4. Top bottom half of each roll with rocket, tomato and a patty. Dollop with mayonnaise, replace each roll top, and serve.