1 Crack the egg into a bowl and whisk well while you add the oils, parmesan and lemon juice. If you're not going to add an anchovy or two, whisk in the salt.
2 Break the crisp lettuce into bite-sized pieces and put into a salad bowl. Drop in the shredded cold chicken and mix to combine. Season with black pepper, to taste.
3 Toast the tortilla chips for a couple of minutes in an oil-less pan over a medium heat.
4 Give the dressing another whisk, pour it over the salad and toss to mix. Add the tortilla chips (and some anchovies, if you like) and toss again before wolfing down