French Onion Soup

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French onion soup – thick, hearty, and bursting with umami flavour, normally from beef broth and cheese.  A vegan nightmare?  Well, not anymore.  After a trip to a French restaurant a few weeks ago with colleagues, during which I jealously eyed their French onion soup, I decided I’d make it myself.  It can’t be that hard, right?  It’s just onion and some stock, right?  Or so I thought, until I started reading about it, and I realised that it relies on beef stock to achieve depth of flavour and also thickness.  It didn’t seem like it would be as simple of just substituting vegetable stock for the beef stock.  What I ended up doing was using a mixture of French onion stock (which seemed appropriate) and mushroom stock (for a hearty flavour), plus some extra flour for thickness (all the recipes I found used flour to thicken the soup, so I just doubled what seemed to be the going amount).

The key here is to make sure your onions are very well caramelised; I like to add a bit of balsamic vinegar when caramelising onions and I think this boosted the flavour even more but you don’t have to.  The cheese toast was the easiest to veganise – I just used vegan cheese!  (I’ve also used nutritional yeast on toast before, too, which you can see in the picture – this is just for the true nutritional yeast lovers, though).  Both ways resulted in a satisfyingly savoury soup, which was perfect for a winter day!  Just don’t make this one for Valentine’s Day or before any hot dates – your breath will be extremely oniony!


French Onion Soup

Serves 2


  • 1 tbsp vegan margarine
  • 1-2 tbsp olive oil
  • 1 kg onions, sliced
  • 1/4 tsp salt
  • 2 tsp sugar
  • 1 tsp balsamic vinegar
  • 3-4 tbsp flour
  • 250 ml white wine
  • 1.25l stock (French onion or mushroom)
  • 8 slices French bread
  • Vegan cheese, grated (I used Mozzarella flavour Cheezly)


  1. Heat the margarine over medium heat in a large saucepan until melted, then add olive oil.  Add the sliced onions and sprinkle with salt.  Cook for 5-10 minutes, then add the sugar and stir to coat.
  2. Cook the onions over medium to medium-low heat, slowly, for 45 minutes or longer, until they are caramelised.  If they begin to burn, turn the heat down.  The key is to cook them slowly, to bring out the flavour and caramelise them.  Stir every 10 minutes or so.  They will begin to stick to the bottom of the pan.  If they stick too much, you can add some wine to deglaze the pan.  Once they begin to go brown and are caramelising, add balsamic vinegar to deglaze the pan and give the onions extra flavour.  Cook for another 3-5 minutes.
  3. At this point,preheat the oven to 230 C to make the cheese toasts.  Add the flour to the onions and cook for 3-4 minutes, stirring.  Add the wine and stock, and turn the heat to high, until the soup begins to boil, then reduce heat and simmer the soup for 20-30 minutes.  It’s important to simmer it to remove any flour-y flavour, and to let it simmer for awhile for the flavour to develop.
  4. While the soup is simmering, make the cheese toasts.  Place the slices of bread on a baking tray lined in parchment paper, grate cheese over the slices of bread, and bake for 10-15 minutes until the cheese melts.  You can also place the toasts under a grill for a few minutes (watch carefully and make sure they don’t burn or set off the fire alarm!).
  5. To serve the soup, ladle into bowls (preferably large bowls) and top with cheese toasts.


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Caitlin Galer-Unti

Hi, I’m Caitlin and I’ve been vegan since 2008 and vegetarian my whole life. Since going vegan, I’ve lived in 4 countries and travelled to over 30! I’ve also published two bestselling vegan books (The Essential Vegan Travel Guide and The Barcelona Vegan Guide) and had my work featured in The New York Times, Vegetarian Food & Living and Vegan Life magazine. I’ve veganised my life and I’m here to help you design your life around your vegan values. 


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