Shining, thick and sweet, this is a sumptuous dressing. Use it for cold potato salads, pasta salads, or terrific salads of canned cannelloni and flageolet beans, cooked mange-tout, French beans, sugar snaps and/or broccoli florets with toasted hazelnuts. Eating salads has never been so good. If you don't eat nuts, just increase the amount of olive oil to replace
the hazelnut oil.

Ideally equipment and ingredients should be warm. If it is a cold day, fill the large bowl with warm water while you measure out the ingredients.

1 egg - the freshest and best quality you can find
1 tbsp Dijon mustard
285ml groundnut or sunflower oil
4 tbsp extra virgin olive oil
3 tbsp hazelnut oil
3 tbsp tarragon or sherry vinegar
100-140ml warm water
salt and white pepper

In the large bowl fitted with the E-disc, whiz the eggs with the mustard.
Mix the oils and vinegar together in a jug and with the motor running; pour gradually down the feeder tube in a steady dribble.
It will be very thick at this stage. Follow with the water to make a creamy dressing.
Check the seasoning, adding a touch of salt and pepper if you like.
Store in the fridge in a bottle if not using immediately. It will keep for up to seven days if the egg was really fresh.