In Africa this is a very common salad that is prepared to be eaten as a side dish with lunches or dinner. See The recipe below;
Dice 1 medium size or large onion. Place the chopped onion in a small bowl and fill it up with water. Add 2 teaspoons salt and stir lightly. Allow it to soak for 30 minutes. Chop 4 to 5 tomatoes, half a cucumber and and a handful coriander leaves very finely.Cut the chilli in half lengthwise and scoop out the seeds( chilli is optional ). Nicely dice 1 avocado. Place the chopped onion and the water in a sieve. Shake the sieve a little to remove every drop of water. Allow to drain for 10 minutes.Transfer the chopped and drained onions, cucumber, chilli, coriander leaves, avocado and tomatoes into a large bowl and stir gently. Add 2 tablespoons of lime juice, salt and black pepper to taste.