Bring a pan of water to just below simmering. Add a little vinegar and use a wooden spoon to stir the water for a few seconds. Remove the spoon and allow the water to calm on top (you don’t want waves; the whirlpool will continue for a while under the surface even though you can’t really see it).
Carefully break an egg into the centre of the water. The circulating water should spin the egg into a nice spherical shape without dispersing too much, if any, of the white.
Use a slotted spoon to carefully scoop under the egg and move it around a little for about 3 minutes until the white is just firm but the yolk still runny.
Make the Toast
While the eggs are poaching, remove the flesh from the avocado and mash with the back of a fork, leaving some lumps for texture.
Toast the sourdough slices and spread with a generous layer of chipotle mayo. Pile on the mashed avocado, top with the poached eggs and sprinkle with parsley to serve