French onion soup is a true classic and rightly so. Here, the recipe is adjusted so that it can be enjoyed by vegans, with the 1.17 Balsamic Vinegar of Modena adding sweetness and sharpness while also adding the depth of flavour that would traditionally come from a meat-based stock. Replacing the molten cheesy crouton is a hearty slice of toast covered with creamy vegan crème fraiche and a thick layer of our tangy, peppery Grape Must Mustard. A note on the onions – they really cannot be hurried and do need around two hours to become incredibly soft, so the recipe does need time, but aside from this, is very simple.
6 small / medium red onions
2 tsp salt
1 tsp plain flour
1 sprig chopped fresh thyme
600 ml vegetable stock
1 tbsp light soy sauce
4 pieces of sourdough / rustic style bread
150g vegan crème fraiche
8 tsp Grape Must Mustard
Peel and slice the onions as finely as possible (a mandolin is ideal for this job). Place a large pan on a medium heat, when hot add the olive oil followed by the onions and salt. Stir so that the onions are coated with the salt and oil. The onions need a long, slow cook so keep the heat on medium till they soften and begin to sweeten and then turn down to low. You do not want any dark caramelised pieces as they will taste bitter, so if you see them darkening turn the heat down straight away. Keep stirring from time to time to ensure that they are not sticking. They will taste good after one hour, but they really do need 2 hours, or even more if you have the time, to ensure that they are completely soft. Always keep the heat on low and keep stirring and eventually they will get there.
When the onions are very soft and sweet, bring the vegetable stock up to a simmer.
Add the thyme to the onions and cook for a few minutes, then add the Balsamic Vinegar. Turn the heat up and keep stirring so that it evaporates and aids the caramelisation of the onions.
Add the flour to the onions and cook for around two minutes, still on low to medium heat, stirring to scrape off anything that sticks to the bottom. Now add about half of the stock and keep stirring to break down any lumps of flour, then add the remaining stock and soy sauce. Turn the heat up so that the soup comes to a boil then turn down to a simmer and cook for 10 minutes.
Taste the soup and add more salt if necessary – it will probably need a pinch because of the variation in strength of stock cubes but taste first then decide.