French onion soup

On a cold night, there is nothing so deliciously warming as French onion soup. Anna Trapido writes that this thick, caramelised broth topped with a gratinated Gruyère cheese crouton is the ultimate in winter comfort cuisine. Legend has it that the soup was created by French King Louis XV (1715 - 1774) who found himself alone at his hunting lodge with only onions, butter and Champagne. The culinary monarch is said to have whipped up a batch of onion soup and the rest is history. Pretty as this story may be, the reality is that the soup is almost certainly much older than Louis XV. Indeed, it bears a striking resemblance to the earliest soups, known originally as "sop", which consisted of a broth so thick it was almost stew, soaked up with large pieces of stale bread.

Whether or not royalty was involved in its creation, French onion soup has come to be associated with cheap, hearty winter meals and is now most commonly linked to the 19th century porters at the Les Halles Market in Paris who were served bowls of the soup to ward off early morning cold. It might seem strange to serve soup at 5am but he who has not worked outdoors in a Northern winter is in no position to judge the gastronomic choices of those who have.

In addition to its warming properties, French onion soup is also delicious and simple to make. Not even the "I burn water" brigade can damage the recipe. The beauty is that the onions are cooked slowly, until the sugars in the vegetable are released. This sweetness is accentuated by a dash of brandy and counterbalanced by the acidity of white wine.

There are only two exceptions to the rule that French onion soup is indestructable. The first is that onions are the star and anything that damages the star will destroy the soup. Time is the only way to bring out the natural sweetness of the onions. Slow sautéing over a medium heat will result in golden perfection. Speed up the process and none of the natural sugars will come out. The second key issue is that your soup can only be as good as the stock you use. If you use a stock cube you will end up with soup that tastes like a Pot Noodle...

Be warned, the soup is gratinated with its cheese topped crouton at the end of the cooking process and it needs to be served the moment that the cheese has melted. Oven gloves are essential to remove the scalding hot bowls from the grill and if you slop the combination of hot soup and molten cheese onto yourself while transferring it to the table you'll need Burn Shield.

Safety warnings aside, this soup is fit for a king and cheap enough for a pauper to produce on a weekly basis. Louis XV was known as Louis le Bien Aimé (Louis the well loved), and with soup as delicious as this it's not hard to see why.

RECIPE

This is a modified recipe, as classic French recipes call for heart-stopping quantities of butter.

50g butter
15ml olive oil
2kg brown onions, julienned into very thin slices
5ml fresh thyme, finely chopped
15ml balsamic vinegar
150ml dry white wine
45ml brandy
2 litres chicken or duck stock
10 baguette croutons (sliced, brushed with
olive oil and toasted until golden)
150g grated Gruyère cheese

Heat the butter and olive oil until the butter melts. Add the onions and gently sauté over a medium heat until they are soft and beginning to caramelise (about 15 minutes).

Add the thyme and reduce the heat to very low.

Cover the pot and cook for 20 minutes, turning the onions occasionally.

Add the balsamic vinegar, mix well and cook, uncovered, for 10 more minutes until the onions are deep golden.

Deglaze the pot with the white wine and the brandy to ensure the caramelised sweet onion goo on the bottom does not stick and burn. Allow all the liquid to cook off.
Increase the heat, add stock and bring to the boil.

Once the mixture is boiling, reduce the heat to a simmer and cook for 20 minutes, skimming any impurities off the top.

Season to taste.

Croutons
Pre-heat your oven grill to a very high heat and place the rack as close to the grill as your soup bowls will allow.

When the soup is done, ladle the hot liquid and onion pieces into individual soup bowls and float a toasted crouton on the top of the soup.

Place a handful of cheese on top of each crouton. Don't worry if you miss the edge of the crouton and some cheese hangs over the sides as this will become crispy when grilled. The crispy cheese bits are inevitably the best.

Place each bowl under the pre-heated grill and allow the cheese to melt, then bubble. Do not allow the cheese to burn, but a few brown spots can add a pleasant
crispy texture.

Serve immediately.