For the avocado and beet salad with citrus dressing, preheat the oven to 200 degrees. Clean the beet, remove any leaves and place on a baking tray. Add a dash of water, cover lightly with aluminum foil and bake for 45-60 minutes until tender.
Let the beets cool, peel and cut into wedges. Place in a bowl, season with salt and pepper. Mix in red wine vinegar and 1 tablespoon olive oil.
Mix shallot cubes with white wine vinegar, lemon and orange juice and a pinch of salt and let stand for 15 minutes, add olive oil and mix well. Finally, mix in the zest and chervil. Season to taste.
Cut the avocados in half lengthwise and remove the seeds. Cut into 0.5 cm thick wedges with the skin, then peel off the skin.
Arrange avocado wedges on plates, season with salt and pepper. Place the beet decoratively on top, drizzle with the dressing. Decorate the avocado and beet salad with citrus dressing with chervil and serve.