Few culinary matters are more vexed than the question of how to make the perfect salad dressing. For such an apparently simple operation, there is remarkably little agreement about how to proceed. Anxiety and debate attend every stage of the process, from ingredients to proportions to the method by which the ingredients are combined. In what proportion should the olive oil be mixed with the vinegar? Is balsamic vinegar preferable to wine vinegar? Should the mixture be emulsified by vigorous shaking in a screw-top jar, or simply mixed with a spoon?
Faced with so many alternatives, it is hardly surprising that most people take the easy route and opt for the bottled variety. But this is a grave mistake. Bottled salad dressings are invariably disgusting. No matter how much care their manufacturers take to make them seem natural and "home-made", there is always that give-away tang, that whiff of chemically assisted emulsification, which immediately identifies them as being factory-made.
At the other end of the scale are the salad dressing zealots. These are people who believe that, when it comes to dressings, there are no shades of grey. There is simply their way of doing things, which is necessarily right in any situation. "Three to one, oil to vinegar," they chant. Such people are invariably blind to the coincidence that their "definitive" method also happens to be the one that their mothers taught them as a child.
In their way, the zealots are just as deluded as those who rely on commercial products. For there is no correct way of making a salad dressing. The best salad chefs are those who look at what ingredients they have and then decide how best to augment them. Salad dressings should perform the same function as pasta sauces: they should enhance the flavour of the primary ingredient (that is, the lettuce or the pasta). In Britain, because most salad ingredients are of such poor quality, we have lost sight of this, and salad dressings have become simply a means to drown the taste of iceberg lettuce and watery tomato.
Given what I have just said, I shall not presume to offer a recipe. Here, however, are a few tips, intended more in a spirit of provocation than instruction.
Balsamic vinegar is overrated. I suspect that its current ubiquity has come about only because most wine vinegars are so bad. Balsamic vinegar has that easy-on-the-palate flavour which means that one can end up putting it with virtually anything. The other day I was eating focaccia and olive oil in a restaurant , and my dining companions insisted on putting balsamic vinegar with the oil. A big mistake. The other thing that is increasingly common is using balsamic vinegar (rather than just olive oil, salt and pepper) to dress a tomato-and-mozzarella salad. That is truly shocking, but again it partly stems from people being used to poor-quality tomatoes.
The weather affects what kind of salad dressing you should make. In warmer climates, a lighter dressing is appropriate. In Britain, our tendency to go for heavier dressings is at least partly the result of our climate. If you were making a green salad in Tuscany, it would be ridiculous to use mustard and sugar, but in Britain it makes a certain sense. The same is true of emulsification: it is perfectly acceptable to shake the dressing in a screw-top jar in the depths of an English winter, but it would be criminal to do so when making a dressing for a rocket salad on a warm summer's day. In general, the colder the weather, the more acid you need. Citrus ingredients, such as lemon and lime, should be used to accompany light salads when the weather is hot.
Make sure that the lettuce is completely dry before dressing. This is less important nowadays, as more and more people buy packs of pre-washed lettuce from the supermarkets. But the combinations are usually rather boring, and your salad ends up tasting like something you'd get in a restaurant. It is best to go to a good market and buy a selection of leaves. But then, after washing them, dry them thoroughly. If you don't, the salad ends up tasting of water.