Chop the tomato and onion finely. Mix together in a bowl.
Add the chopped herbs and pepper.
Whisk vinegar, oil and salt very well.
Add this to the tomato onion mixture. Mix well. At this stage you can leave the vinaigrette covered in the fridge for 1 hour to allow the flavours to infuse. Or else use immedaitely.
Cut the avocado into half. Remove the seed.
Spoon the mixture into each half of the avocado and serve.
Serve on its own or with a slice of toasted bread.
Notes
If you need to serve this dish as a starter to guests, you can keep the tomato mixture ready in advance in the fridge but do not add the salt. Add salt just before serving.
If you are working with more avocados, then brush each half with lemon juice to prevent it from turning black.
Instead of onion or shallot can use spring onions, chopped finely.
Can add a tsp of finely chopped walnuts or pine nuts for an extra special treat. Remember to toast them slightly in a pan.
For chilli lovers, add finely chopped green chillis at your risk.
As a tummy filler for ekadashi day, omit the onions. Can add chopped olives.