I have resumed work on my cook book. Here is what I have to say about soup in general and vichyssoise in particular:
Soup is underrated and undeservedly unfashionable. Few people choose it, perhaps because it seems a little boring, but most people enjoy it if it is served to them.
The easiest way to get decent soup is to buy it. Go for the most expensive carton in the refrigerator in the supermarket, or if none, the most expensive tin on the shelf. In the summer, a cold vichyssoise or gazpacho is hard to beat. In the winter, soups with cream or potato are particularly warming. Lobster bisque is good any time. Do not heat soup you buy in the microwave, but in a saucepan; that way, the smell of the soup will proceed it, which is important.
There are two tricks to serving soup. First, dress it up with a dollop of thick cream or, even better, sour cream or yoghurt and perhaps a bit of chopped coriander (always a bit classier than parsley). Second, serve it with some decent fresh bread and perhaps some butter.
If you are serving soup as a first course of dinner, go for rather small servings – about half what it recommends on the packet per person – otherwise it will get in the way of the rest of meal. Conversely, a much more generous serving coupled with bread and butter makes a good lunch of itself, or can be followed simply by some bread and cheese.
For dinner, incidentally, skip the bread and butter and instead sprinkle the soup with freshly made hot croutons. These, you do have to make yourself. Chop some bread (preferably fresh, but this is not quite so important as if bread is served as it is) into cubes no bigger than the tip of your finger. Fry the cubes in a generous slug of very hot olive oil — it needs to be more or less smoking before you put the bread in the frying pan. Add quite a lot of salt, and stir the cubes of bread around for a couple of minutes serve till or so until the outside of the bread is browned, or even slightly charred. There are two things to watch for. First, the bread tends to fly out of the frying pan if you stir it around too fast, so keep stirring slowly but continually. Secondly, the process tends to make an awful lot of smoke. If it doesn’t, your pan is not hot enough, and you will end up with nasty little bullets. So open a window or two or get the extractor running full blast; unlike the smell of the soup, the smell of croutons being fried is not going to help your meal. By the time your croutons are ready, the soup should already be in the bowls; add the croutons directly from the hot frying pan, and they should sizzle gloriously for a few moments when they hit the soup. Depending on the sort of soup, a few shavings of parmesan or other very hard cheese on top of the croutons can be good.
You will need
- A blender or a liquidiser. If you do not have one of these, turn over and try something else. Life is too short to be making vichyssoise by hand.
- A sizeable knob of butter
- ½ lb onions (that is about 2)
- 1 lb leeks (this is about 4)
- 1 lb potatoes (that is about 6 smallish ones)
- 2 pints chicken stock (either in a cardboard box, or just made with a stock cube)
- ¼ pint cream
- A dollop of plain yoghurt
For some recipes, the quantities need to be exact. This is not one of them. In fact, Elizabeth David suggests leaving out the onions altogether, but I am not with her on this one. These quantities will make enough for about 8 people. Or 4 people for 2 days; it keeps perfectly well in the fridge for a couple of days or so.
Start early – this will need a least a couple of hours in the fridge to be cold enough to serve.
The best thing to use is a decent sized pan with a heavy enough bottom to allow you to fry in it and also with enough capacity for the whole thing. Put in the butter. While the butter is melting, smash up the onions as small as you can in the blender, and then fry them for a couple of minutes. Whilst that is happening, cut away and chuck the green bits of the leeks, and the rooty ends, and smash the remaining white parts up in the blender. At the risk of stating the obvious, do not bother to wash the blender after smashing up the onions. If you even thought of washing the blender out after smashing up the onions, you probably should not be reading this. But do stir the pot. Add the leeks, and stir the pot again.
Smash up the potatoes as small as you can in the blender, and then add them to the pot. You are not aiming here to caramelise any of these ingredients: rather to just soften them up. This frying process takes the sharpness off them; otherwise they compete with the cream which comes later. So before anything goes brown, add the stock (or just water, of you are planning to then lob in a stock cube). I usually do this slowly, to make sure that any sticky stuff in the pan gets thoroughly dissolved before flooding it, but this is probably just habit. Then leave it to simmer for ½ hour. This is what cooks the whole thing.
After you have done that, you will need to cool it down. Obviously, it is very dumb to put something large and piping hot in the fridge – that will just heat up the fridge. So you can just leave it for an hour to cool down. Alternatively, if you are impatient, you can put the pan in a sink of cold water; that will cool it down enough to put in the fridge in about 10 minutes.
If you are using a liquidiser, this is the time to puree the thing. Do not be tempted to put it in the liquidiser whilst it is hot. I tried this one, and it virtually exploded. There are probably small bits of vichyssoise lodged to this day inside the kitchen radio. If you are using a blender, blend away until there are no more lumps of anything. Depending on how big your blender is, you might have to do this in batches.
It needs to go in the fridge for at least a couple of hours, and preferably more. Stir in the cream just before serving.
Now, it has to be admitted that, what with the cream and stuff, this soup, delicious as it is, is hardly low calorie. It was invented in America, albeit by a Frenchman, Louis Diat, at the Ritz-Carlton in New York, in the summer of 1917. That fact that Louis was in the Ritz-Carlton in New York whilst most Frenchmen were slogging it out in the trenches suggests that he would not have cared too much about the calories. But, if you or any guests are worried by that sort of thing (the calories, not the World War I), plate up in the kitchen, add a spoonful of low-fat yogurt to the centre of each serving, and then sprinkle some chopped chives over the yoghurt. This will not make it any less fattening, but it will give that illusion. Which might, depending on who you are trying to impress, be useful.
This is not a soup for croutons. Freshly made breadsticks are good, or sourdough toast.
 French Provincial Cooking, page 205.