Halve the avocado, remove the core, cut a lattice in half with a knife and remove the cubes with a spoon. Cut the onion into fine strips. Wash and dice the remaining vegetables. Chop the chives.
Put all ingredients in a bowl and season with sea salt, coarse pepper and lemon juice. If you like, you can add a pinch of sugar.
Put the salad on a plate. Dice the feta and add to the salad. Roast the pine nuts in a pan without oil on medium heat and sprinkle over the salad. Garnish the salad with balsamic cream and serve.