
**This post was developed and written by Nancy Gammack, RD when she was a dietetic intern and volunteer for Ignite Nutrition.
It wasn’t as easy as I thought it would be to make a low FODMAP soup. Many of the ingredients found in recipes or store-bought soups are high in FODMAPs. Including garlic and onions, and broths and stocks. These are all common soup base ingredients. This formed a unique challenge for me as an IBS dietitian. But, with a little research and a lot of experimenting, I found the perfect combination of ingredients to bring you a simple, yet delicious homemade parmesan tomato soup!
What is the best onion substitute?
Fresh fennel was the winner as the substitute for onion! Fennel is a green and white herb that has a distinct liquorice flavour when eaten raw. Sautéed and browned in butter, the flavour is softened and provides a good base for this tomato soup. Alongside the diced tomatoes it also produces a perfect texture for the soup.
Instead of garlic powder, ground coriander and fresh basil are used. So, rest assured, this dish is still full of a pleasant aroma.
Add this soup to your back pocket for a simple soup to make if you don’t want to worry about consuming a store bought product that may include FODMAPs! Looking for another low FODMAP soup option? Try this low FODMAP broccoli cheddar soup which packs a punch of delicious flavour!

How do you pimp up tomato soup?
There are many things you can add into tomato soup to give it that extra boost of flavour or texture. For example, some toasted pumpkin seeds add a great nutty crunchy flavour. A drizzle of garlic infused oil works wonders for the flavour. Another option is to add some fresh chopped green onions ontop.
Are canned tomatoes FODMAP friendly?
Canned tomatoes are FODMAP friendly. They are well tolerated in serving sizes of of 2/3 cup – 1/2 cup per meal. This low FODMAP parmesan tomato soup is a great option for enjoying tomatoes in a FODMAP friendly way.
Love this low FODMAP recipe as much as we do? Our collection of low FODMAP recipes were created to help you navigate the low FODMAP diet. Many of our patients have tried implementing the low FODMAP diet on their own. However, this diet should be conducted with the support of a registered dietitian. At Ignite Nutrition we offer one-on-one nutrition counselling to help you start on the low FODMAP diet with guidance.
Low FODMAP Parmesan Tomato Soup
Ingredients
- 1.5 tbsp butter
- 2 cups of chopped fresh fennel bulbs
- 14 oz of unsalted diced tomato
- 21 fluid oz of unsalted puree tomatoes
- ½ cup of CAMPBELLS Chicken broth
- ½ cup fresh chopped basil
- 2 tsp coriander
- Fresh grated Parmesan to taste
- Salt and pepper to taste
Instructions
- Wash, remove leaves and dice fresh fennel. Set aside.
- Melt Butter in saucepan, and add fennel.
- Sauté at medium-high until golden brown, about 10 minutes.
- Add in diced tomatoes, puree tomatoes, chicken broth, and ground coriander.
- Bring to a boil, and then lower heat and simmer for 20 minutes.
- Remove from heat and add Finely chopped basil leaves. Stir.
- Serve with grated parmesan on top.
- Enjoy!
Notes
- Pair this soup with a warm grilled cheese sandwich on sourdough, or a Tuna melt to add a little protein
- Store the leftovers in pre-portioned containers to make quick grab-n-go lunches.
- Try changing the quantities of purée to diced tomatoes depending on your thickness preferences
- Puree in a can of lentils for added vegetarian source of protein!
**Last reviewed February 2022 for Monash FODMAP portions

Categorized: Gluten-Free, Healthy Eating, Low FODMAP, Lunch, Main Dish, Nut-Free
I thought fennel bulbs were a no no in Fodmap
Up to 3/4 cup per serve is low FODMAP 🙂