This vegan mushroom onion soup is delicious, fast, gluten-free, and vegan AIP friendly! And it’s so easy to make (whether you have an Instant Pot or make it on the stove).
Packed with both onions and mushrooms, it’s also incredibly good for you! Onions of course are great for your immune system, containing vitamin C, zinc, selenium, and quercetin, an antioxidant that has antiviral properties. And baby bellas (which are actually crimini, or cremini, mushrooms) also are immune boosting!
This recipe is also incredibly clean, having only 4 ingredients unless you count the bay leaf and thyme, in which case it’s only 6 ingredients. In part this is because it calls for mushroom broth, rather than vegetable broth (because one of us has a carrot sensitivity, and there is carrot in pretty much all prepared vegetable stock, and so far we haven’t felt the urge to make our own carrotless vegetable stock, because the Pacific brand organic mushroom broth is so darned good).
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Like many of our recipes, this recipe came about based on a sudden craving, and what we had in the house. The craving was onion soup, and we had plenty of nice organic onions but we also had a bunch of baby portobello (or ‘portabella’ – both are correct) mushrooms that needed to be used up. So this mushroom onion soup was born.
This soup is almost a meal in itself, although it would be awesome sided with a salad, or a gluten-free bread with a bit of vegan butter to dunk in your soup! One of us also crumbled up a veggie burger into it and said that it was wonderful.
Here’s how to make it.
Vegan, Gluten-Free Mushroom Onion Soup
1 quart mushroom broth (we love the Pacific brand available on Amazon)
2 large onions – very thinly sliced
4 cups sliced mushrooms (we use baby bellas for a heartier flavor)
1 large bay leaf
1/2 – 1 teaspoon dried thyme
1/8 cup Balsamic vinegar (you need a good quality one for this, otherwise omit it)
If you are using a stove top pot, pour enough olive oil in to completely cover the bottom, and put it on medium heat. If you are using an Instant Pot, pour enough olive oil in to completely cover the bottom of the inner pot, and turn it on to Saute on the lowest setting.
Put all of the onions in the pot, and saute over medium heat, stirring occasionally. You want all of the onions to get cooked until they are going translucent and cooked through, but not browning (although having some of them brown would add another flavor dimension that could be delicious!)
When the onions are almost done, add the balsamic vinegar, mix it in well, and continue cooking for a minute or two.
Now add the mushrooms, mix well, and cook for another few minutes, to get the mushrooms heated up.
Add the broth, the bay leaf, and the thyme, and then salt and pepper to taste.
If using an Instant Pot, turn off the pot, lock on the lid, close the vent, and set it to manual pressure for 5 minutes, and then let the pressure release naturally.
If cooking on the stove, bring to a boil, lower the heat and simmer for about 20 minutes, or until the mushrooms are done to your liking.
Delicious and Nutritious!
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