French onion soup will taste even better if you add a splash of 1 ingredient

Soup season is officially upon us and one chef is urging home cooks to give some attention to a classic French dish. French onion soup is one of the most recognisable meals to have during the winter season.

Chef Matthew Ryle recently shared some of his top tips for perfecting some classic French dishes in the latest edition of Good Food magazine, proving just how easy it is to recreate them at home. He described French onion soup as the "ultimate comfort food", flavoured with rich notes of caramelised onions, beef stock, and piled high with lashings of grated cheese. However, to take it to the next level, the chef revealed he adds one unusual ingredient to help the onion flavours "sing".

He said: "A staple in restaurants across France, the recipe actually originated as a humble peasant soup made with just onions, stale bread and water. Today's version might be a bit fancier, but this is still simple to make at home."

Matthew's secret ingredient? Soy sauce.

He told Good Food: "The secret ingredient to this soup is time, as the onions need to be cooked very low and slow. The more caramelised, the more flavour they'll have.

"Making your own stock will result in the most authentic-tasting soup, but shop-bought stock will do the trick as long as your onions have received enough love. It's not traditional, but my other secret is a splash of soy sauce, which adds richness and makes those caramelised onion flavours sing."

So if you're looking for a warming, hearty soup to enjoy throughout the winter months, this is how you can recreate Matthew's French classic at home.

Ingredients

• 1.5kg onions, finely sliced
• 100g butter
• Three garlic cloves, crushed
• Three bay leaves
• Few thyme sprigs, leaves only
• 300ml white wine
• 1.3 litres good-quality beef stock
• 50ml soy sauce
• ½ day-old baguette
• 250g gruyere

Method

Cook the onions in the butter over a low heat in a wide, heavy-based pan. After 10 minutes, add a pinch of salt, the garlic and bay leaves.

Cook, stirring regularly, until the onions are caramelised and brown, about 45 minutes. Add the thyme and pour in the wine.

Bring to a simmer and continue to cook until the wine has reduced by half.

Add the beef stock and soy sauce and gently simmer for around 10 minutes. Meanwhile, cut the baguette into 2cm-thick slices and grate the gruyere.

Heat the grill. Check the seasoning of the soup, adding salt and pepper if required, the ladle into ovenproof bowls that can go under the grill.

Top with the baguette slices and mound high with grated gruyere, dividing it evenly between the bowls. Place under the hot girl until golden brown and bubbling, then serve.