It might be summer here in Australia but I’m already anticipating soup season. To add to my low FODMAP soup collection, today we’re making low FODMAP lentil soup.

You might be thinking that ‘low FODMAP’ and ‘lentil’ shouldn’t be in the same sentence. Think again! Thanks to appropriate serving sizes and canned lentils, this soup is suitable for those on the low FODMAP diet.

Low FODMAP lentil soup

This soup is made from a simple base of leek greens, spring onion greens and chopped carrots. Think of this as your low FODMAP mirepoux or soffrito – the base of the soup. From there, we add flat leaf parsley, tomato paste and dried herbs for flavour. Gluten free dark miso paste and nutritional yeast are an (optional) umami hit and the canned lentils are for protein. I like to finish my lentil soup off with 1/2 – 1 bunch of Tuscan kale for greens but any greens would work here.

This low FODMAP lentil soup is vegetarian or vegan, grain free and nut free. It takes 30 minutes to make, so it’s a great weeknight dinner. Unlike minestrone, there’s no pasta to go mushy over time, so this soup makes for a great freezer or meal prep option, too.

Tips for your low FODMAP lentil soup

The biggest tip I could give anyone for working with leek greens is to wash between every single leaf. You would be amazed at how much dirt lurks in the inner leaves of a leek. Peel them off and wash them one by one to ensure your soup is not gritty.

There is a section below specifically on the lentils and ensuring you get a low FODMAP serve of lentils.

However, I recommend draining and rinsing your canned lentils well. Canned lentils are lower FODMAP because the FODMAPs leech out into the canning liquid. As a result, you want to wash that right off.

I love using garlic infused ghee for the best of my low FODMAP lentil soup. I find the flavour carries through to the final dish, unlike with garlic infused oil. If you don’t want to use ghee or need a vegan option, however, adding garlic infused oil to the top just before serving does add a garlic hit. You can also add some pickled garlic, which is newly low FODMAP (my recipe can be found here).

Because lentils contain starches, the soup will thicken as it cools. If you’re using it for a meal prep situation, add some water or stock before reheating.

Notes on the lentils

Because the lentils are really the main FODMAP concern in this soup, they’re worth chatting about. Firstly, I have used canned brown lentils for this soup. As of November 2025, Monash says that canned lentils are low FODMAP in serves of up to 75g per person. In 76g serves, they contain moderate amounts of GOS.

A standard can of lentils in Australia is 400g net weight. However, the total amount of lentils once drained is approximately 240g.

So, 240g of drained lentils needs to serve 4 people. This soup serves 4-6 depending on what you serve it with and your appetite.

FODMAP notes

These FODMAP notes were last reviewed in November 2025. They will be periodically reviewed to ensure they remain up to date with Monash research.

Spring onion greens and leek greens are low FODMAP and a great way to add onion flavour. Spring onion greens are low FODMAP in 75g serves and contain moderate amounts of fructose in serves of 97g or more.

Leek greens are low FODMAP in serves of up to 500g per person.

Tomato paste is low FODMAP in serves of up to 80g per person. In 81g, it contains moderate amounts of fructans.

Tuscan kale is low FODMAP in serves of up to 221g per person. In 222g serves, it contains moderate amounts of GOS.

I have tried to keep everything else low or no FODMAP. Make sure you use a low FODMAP stock if you’re using stock. I have a recipe for low FODMAP vegetable stock here.

Optional add ins

The sky is the limit when it comes to adding in vegetables to this soup. You can substitute kale for another hardy green, add some zucchini, or really throw in any bottom of the fridge you’ve got going. I daresay some finely cubed pumpkin would go down a treat.

You can also another herb that works for you. I’d recommend basil or chives, perhaps a small amount of sage.

Personally, I like to finish my soup with a generous grating of vegetarian parmesan and some garlic infused oil. I have a list of vegetarian parmesan brands in Australia (yes, they exist). I have also recently tried Green Vie vegan parmesan and I think it’s the best vegan variety I have tried so far.

Because I really enjoy this soup, I am going to work on a curried version as well. Think part low FODMAP daal and part soup.

More low FODMAP vegetarian or vegan soup recipes

• Low FODMAP leek and potato soup
• Low FODMAP pumpkin soup
• Low GODMAP minestrone
• Low FODMAP vegan ‘chicken’ noodle soup
• Low FODMAP Moroccan spiced pumpkin soup

Low FODMAP lentil soup

Vegetarian, vegan option

Serves 5-6

*Measures are in Australian tablespoons.

1 Australian tablespoon = 4 Canadian, US and New Zealand teaspoons or 3 1/2 British teaspoons

5 from 1 vote

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Prep Time 15 minutes mins

Cook Time 20 minutes mins

Course Main Course

Cuisine Food Intolerance Friendly

Servings 5 people

Ingredients

  

1x2x3x

For the soup:

• 60 ml (3 tablespoons)* garlic infused ghee or olive oil
• 2 large leek greens thoroughly washed and sliced thinly
• 50- 75g spring onion greens, sliced
• 1/2 bunch flat leaf parsley soft stems and leaves reserve remaining 1/2 for serving
• 50 g tomato paste
• 300 g carrot cut into small cubes
• 1 – 1 1/2 litres (1000-1250ml) water or low FODMAP vegetarian stock
• 1-2 tablespoons* nutritional yeast
• 1/2 – 1 tablespoon* gluten free dark miso
• 2-3 teaspoons dried sage leaves
• 2-3 teaspoons dried oregano
• 1 – 1 1/2 teaspoons salt to taste to taste if you use stock
• Fresh pepper to taste
• Squeeze of fresh lemon juice
• 1 x 400g can brown lentils drained and rinsed
• 1/2 – 1 bunch Tuscan kale or other hardy greens woody stems removed and chopped relatively finely

To serve (optional)

• Vegetarian or vegan parmesan
• Garlic infused oil
• Extra lemon juice

Instructions

 

• Heat the ghee or oil over a medium heat in a large soup pot. Once warmed, add the leek and spring onion greens and cook for 3-5 minutes until softened and fragrant.
• Add the parsley and stir to combine.
• Add the tomato paste and dried herbs and stir to combine. Allow the tomato paste to caramelise for a minute or two before adding the carrots, water or stock, remaining flavourings and lentils. Cook for however long you’d like – you can leave the soup cooking away, or just until the vegetables are tender. I prefer just tender vegetables. Do whatever you prefer, noting you might need to add more liquid (and thus perhaps more flavourings) if you cook your soup for a longer time period.
• About 5-10 before serving add the chopped kale. This way it will retain it’s lovely green colour and a bit of bite.
• Adjust for seasoning and lemon juice before plating up. Serve with the remaining parsley, and some parmesan and garlic infused oil if you like.

Notes

• To make this lentil soup vegan, use oil instead of ghee and a vegan parmesan. 
• You can find my Low FODMAP vegetable stock recipe here.
• See the body of the post for FODMAP notes. 

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