Put the egg yolks, vinegar, mustard and salt into a bowl
Whisk until they double in volume
Continue to whisk as you slowly pour the oil in
Don’t add the oil too quickly – it should “disappear” into the egg yolk mix almost on contact
As you get close to all the oil being added the mayonnaise becomes very thick. You may have to stop and start pouring to allow the oil time to whisk in
Store in a covered container in the fridge and use within 5 days
Back in the late '80s and '90s the UK egg industry had a serious salmonella problem. That’s no longer the case, but eggs still haven’t lost their notorious reputation. For most people fresh, raw egg yolk is perfectly safe to eat. But as a precaution, infants, the very elderly, pregnant women and anyone with a compromised immune system shouldn’t eat raw eggs. Luckily you can buy pasteurised egg yolk in most supermarkets.