Peel avocado, remove pits, cut avocado into cubes and sprinkle with lemon juice.

Peel beet, slice and dress with 1 tablespoon of oil. Cut cucumber into thin slices, shred celery.

To prepare sauce, whisk oil with salt, pepper, vinegar, sugar, add grated zest and the remaining lemon juice.

Put prepared ingredients in the salad bowl, pour with the sauce and season with seeds.