Whisk the yolks with the garlic, mustard, vinegar and salt and pepper.
Slowly add the oils in a steady stream, continuously whisking the whole time. If the mixture is too thick, add a little hot water and continue whisking in the rest of the oils.
Add some lemon juice and more salt and pepper to taste.
Serve with Cos lettuce and Parmesan shavings for a modern twist on a Caesar salad. It’s also delicious served with seafood or French fries.