French Onion soup – vegan recipe (with a vegetarian option)

By lucylox on January 23, 2025

Vegan version with garlic 'butter' croutons

I've always wanted to make a friendly version of French onion soup, it's such a classic and just the thing on a cold January day. Usually it's made with an intense meaty stock and tons of cheese so i did wonder if this was one of those recipes where i wouldn't get amazing results.

My mother in law is French and I always remember her talking about how her grandparents in rural France would eat onion soup nearly every day, so i had to do justice to this French classic and make my friendly version as delicious as possible.

Vegetarian version

Turns out i really didn't need to worry, the oniony soup is packed so full of flavour that it really doesn't need anything meaty to make it superb (well i always think that but D ate a fantastic French onion soup just the other day at Cafe Francois in Borough Market and he said my version tasted just as good 🙂 )

You do need to take time with cooking the onions down slowly and gently until you have an unctuous soft onion mix, then add plenty of umami flavours to ramp up the flavour and you'll have the most divine vegan French onion soup.

The Moosewood Cookbook by Mollie Katzen is book 3 of my 25 in 2025 cookbook challenge. This has long been a favourite, I think I bought it way back in the 90s when i first became vegetarian - yes it's very much old school vegetarian with lots of reliance on eggs and cheese but you can make many of the recipes friendly, and it's the kind of vegetarian food i find comforting and homely. I feel you don't get books like this anymore, with the hand drawn illustrations and handwriting typeface. Whilst i do love the more polished cookbooks of now, there's something friendly and cosy about this style of book.

Have you got the Moosewood cookbook, do you rate it? I particularly like the salads and some of my favourites started their life as Moosewood recipes and have morphed over the years to my variations that can cater for our whole family.

As The Moosewood Cookbook is book 3 of my 25 in 2025 cookbook challenge, I have used their French onion soup as the basis of my recipe, but with plenty of tweaks and alterations.

Usually French onion soup is topped with a large crouton that is drowned in an Alpine cheese like Gruyere or Comte and in my vegetarian version i've done just that with very finely grated Gruyere (just make sure it's a vegetarian version with no animal rennet used). I found it easiest to melt the cheese onto the croutons and then add an extra handful of finely grated cheese on top.

With cheesy croutons

For a really delicious dairy-free and vegan option toast the crouton with plenty of 'garlic butter' on top and you really won't miss the cheese! You could add dairy-free cheese but i personally find it very overpowering in it's cheesiness and felt it overwhelmed the soup. The garlic croutons do the same job as the cheesy ones - they soak up the delicious soup and go soggy underneath but keep some of the toasty bread top. It's a delicious alternative and i reckon it could take off, who needs dairy anyway!

French Onion Soup - vegan (with a vegetarian version)

a rich and comforting umami soup topped with a flavourful crouton dairy-free, egg-free, nut-free, sesame-free, can be gluten-free, vegetarian and vegan (vegetarian version contains MILK) serves 2

2 tbsp olive oil
2 onions (finely sliced)
1/2 tsp salt
1 tsp dried thyme
1 tsp Dijon mustard
50 ml white wine
300 ml vegetable stock
1 tbsp soy sauce
1 tbsp Hendersons Relish (or vegetarian Worcestershire sauce)

to top

4 slices ciabatta or baguette
2 tbsp garlic butter (for the vegan version)

In a heavy bottomed sauce pan, heat the oil to medium heat and then add the sliced onions and salt.
Cook on low to medium for 15-20 minutes, stirring often, until soft and golden
add the thyme and Dijon mustard and cook for a further two minutes.
pour in the wine and bubble furiously to reduce
Then add the stock, soya sauce and Hendersons relish. Lower the temperature and simmer for 10 minutes.
Taste and adjust the seasoning. Keep warm.
Meanwhile toast the bread slices on one side under a grill.
Turn over and slather with either the garlic butter, return to the grill and toast until golden.
Pour the hot soup into two bowls and top with the croutons

Note: it's very hard to find sesame-free baguettes in the UK, so i recommend using ready to bake ciabattas instead

For the vegetarian version: top the croutons with 20g finely grated gruyere and melt under the grill. Place onto the soup and add a further 20g gruyere on top

For a gluten-free version: use gluten free bread

Soup, starter

French