1. Peel the lemon with a small knife,taking care to remove all of the white pith.
2. Remove any pips and finely chop the flesh. Place in a food processor and add 3 tbsp of oil,the anchovy fillets,garlic and chilli. Process until well combined.
3. Keeping the motor running,gradually add the milk,about ½ tbsp at a time. (If you add the milk too quickly,the dressing may split.)
4. When all the milk is incorporated,add about 1-2 tsp of warm water so the dressing is of pouring consistency.
5. Bring a saucepan of salted water to the boil. Blanch the asparagus until just tender,about 2-3 minutes. Drain and refresh in iced water. Drain again.
6. Dress the asparagus with remaining olive oil and season to taste.
7. Place some of the anchovy dressing on a large share plate,pile the asparagus on top,then top with watercress. Spoon over the remaining dressing and scatter over the hazelnuts.
Suggestion:Serve with Neil's beef chuck and pea pot pies