Whisk the oil and vinegar together and season with salt and pepper.
Slice the flesh of the avocado in a criss cross pattern, then pour the dressing into the hole left by the pit/seed.
Eat straight away.
Avocado - both Hass avocado and Shepherd work well. The avocado needs to be ripe, to test give it a gentle squeeze - it should give, but not feel mushy.Olive oil - extra virgin olive oil is the best for this dressing, but if you don't have it, a regular olive oil will work too.Wine vinegar - both white wine vinegar and red wine vinegar work well in the vinaigrette. White vine vinegar can be a little stronger, it is up to your personal preference and what is in your kitchen cupboard.