- Combine lemon segments and oil in a small bowl. Set aside for 15 minutes.
- To make the sauce, combine all the ingredients in a bowl and set aside.
- Place lettuce cups on a large platter.
- Cut the prawns into chunks about 1½ cm-thick. Cut the avocado into 1cm pieces.
- Divide prawns, tomatoes and avocado among lettuce cups.
- Spoon over some of sauce. Spoon over some of the lemon segments. Scatter with chives.