Slow cooker French onion soup

Want a healthy slow cooker French onion soup that is easy to make? He may be biased, but my boyfriend thinks I make the best French onion soup in the world. If only he knew it is such an easy French onion soup recipe.

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How do you make French onion soup? I am a massive fan of slow cooker recipes. There’s nothing better than coming home after a long day at work, or a day of exploring, to the warming smell of French onion soup. 

French onion soup recipe

All methods serve 4 large portions.

Equipment

So, what will you need to make the slow cooker onion soup recipe? Of course, a slow cooker is essential, and it is always recommended that you pre-heat it before you start assembling the ingredients.

Recipe 1: French Onion without wine

French Onion Soup Ingredients

  • 12 small white onions, sliced 
  • Tbls of sweetener
  • Tbls of balsamic vinegar
  • Beef stockpot or stock cube
  • White wine stockpot
  • Tbls Worcester sauce
  • Tsp of dried thyme
  • ½ tsp of mustard powder
  • 4 crushed garlic cloves or tsp garlic powder
  • Tbls of cornflour

Method

  1. Slowly fry the onions with the sweetener and balsamic vinegar. This will need to be done over low-medium heat until the onions are sticky. (This is what is going to get the flavour into the dish!)
  2. Mix the cornflour into a paste with a tbls of water
  3. Transfer the rest of the ingredients to the slow cooker with 750ml of water
  4. Cook for 3 hours on high

Slimming World friendly French onion soup

I follow Slimming World* and this French onion soup with no alcohol is definitely ideal for a healthy eating lifestyle. The healthy French onion soup is packed full of speed and is 1/2 Syn per portion. Check out my Slimming World journey.


Recipe 2: Traditional French Onion soup

French Onion Soup Ingredients

  • 12 small white onions, sliced 
  • Tbls of brown sugar
  • Tbls of balsamic vinegar
  • Knob of butter
  • Beef stockpot or stock cube
  • 250ml of sherry
  • Tbls Worcester sauce
  • Tsp of dried thyme
  • ½ tsp of mustard powder
  • 4 crushed garlic cloves or tsp garlic powder
  • Tbls of cornflour

Method

  1. Slowly fry the onions with the sugar, balsamic vinegar and butter. This will need to be done over low-medium heat until the onions are sticky. (This is what is going to get the flavour into the dish!)
  2. Mix the cornflour into a paste with a tbls of water
  3. Transfer the rest of the ingredients to the slow cooker with 500ml of water
  4. Cook for 3 hours on high

Don’t have any sherry? Substitute for sherry in a French onion soup is, of course, white wine. You want to pick dry ones such as a Sauvignon Blanc, Pinot Grigio or Chardonnay.


Welsh Onion Soup with Rarebit Crouton at Thomas Restaurant in Cardiff Bay – I love French onion soup, and if it’s on the menu when out, I usually get it as a starter

Gluten free French onion soup

Both methods of my slow cooker French onion soup can easily be made gluten-free. To thicken the soup, replace the cornflour with rice or almond flour. Again, mix this with a tablespoon of cold water and add to the soup.

Vegetarian or Vegan onion soup

Both of these methods can be made vegan friendly. The beef stockpot can be replaced with a vegetable one. You can also use an Oxo Vegan Beef flavoured stock cube, or Massel 7’s vegan bouillon stock cube. You can leave the Worcester sauce out, or use the Bonson Organic vegan Worcester sauce. You will also need to use a butter alternative if you are using method 2.

Can you make French onion soup with red onions?

Of course! Red onions do tend to have less sweetness, but still taste great when slowly sauteed. Sometimes I’ll do a mix of white and red.

When on holiday in Mexico, our French onion soup was served with a pastry top

History of French onion soup

I wanted to know where the dish originated, and if it genuinely is French? Onions have been popular as far back as Roman times. Throughout history, they have been seen as the food of the poor. The modern version originates from Paris in the 18th Century, being made from beef broth and caramelised onions. Today it is eaten all over the world, with it being served with a crusty crouton and cheese in Europe and a melted cheese top in the US and Canada.

The slow cooker French onion soup recipe is in no way connected, affiliated or endorsed by Slimming World. Every effort has been made to give you the correct Syns and information, but I would encourage you to double-check these for yourself.


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