A dairy-free, roasted cauliflower soup that is full of warm spicy flavors. This bold umami recipe is the antidote to a cold night or a much needed pantry clean-out.
How are you with leftovers? I mean really using things that are potentially on their last legs? Vegan Cauliflower Soup came from doing just that. This creamy (non-dairy), roasted cauliflower soup will win over anyone in your house who isn’t a fan of leftovers.
Like my leftover averse husband.
I know. He’s married to a food blogger.
What to do with leftovers
However, he did give this Vegan Cauliflower soup a big thumbs up. Maybe it’s because he didn’t know (until now) that this recipe was created from a bunch of leftover roasted cauliflower.
And that’s what’s beautiful about knowing basic cooking techniques, like making this soup. You have the power to transform something “formerly new” into something newer. Like Thrillist suggests, one of the best attitude adjustments cooks can make regarding leftovers is to start thinking about them as ingredients.
So —let’s get to some attitude adjusting.
One unique Cauliflower Soup
Why is this cauliflower soup different? One word.
Umami is called the fifth taste and it naturally occurs in foods like red meat, tomatoes, Parmesan cheese, mushrooms and more. And our pals at Trader Joe’s have made it extra easy to add umami to dishes (especially if we know someone who might not be eating one or more of those umami-rich ingredients) with their Mushroom and Company Mulitpurpose Umami Powder and Seasoning Blend. Trader Joe’s mushroom powder doesn’t taste like mushrooms but gives you all the mouthwatering umami that mushrooms have to offer.
How to make creamy cauliflower soup
You can be eating this soup in under 20 minutes if you have leftover roasted cauliflower. If not, add another 20 minutes to that estimate.
- Roast your cauliflower until it’s golden brown
- Saute a combo of vegetables. Many soup bases start with a trio like chopped onion, celery and carrots. In Italian cooking, this is called a soffritto. We are using onion, garlic and cauliflower. You could add carrots for a little sweetness, especially if you have some you need to use up.
- Season the vegetables with a blend of spices and herbs, gently warming them to allow them to bloom and release their flavor.
- Simmer the soup base to marry everything together.
- Blend and bring all the ingredients together to make a smooth texture that is balanced in flavor and no ingredient standing out too much or too little.
Herbs and spices
Trust me. This is no bland cauliflower soup. Between the umami powder and the lemon juice and zest, it makes for a hearty, comforting bowl of soup. And spicing things up with a little cayenne or hot chili powder is more than acceptable.
If your pantry doesn’t have one of the spices in the recipe, you definitely can go rogue. Here’s a starting list of spices and herbs that play nice in a vegan cauliflower soup.
- Chili powder
- Fresh Parsley
Safety Tips for Pureeing Hot Soups or Sauces
Danger, Will Robinson. When it comes to blending hot mixtures, there’s a few things you need to know:
PLEASE – DO NOT PUT THE CENTER BLENDER CAP ON THE BLENDER’S LID. OTHERWISE, THE BLENDER WILL EXPLODE AND YOU WILL HAVE CAULIFLOWER SOUP EVERYWHERE AND POSSIBLY BURN YOURSELF.
- Pour the hot mixture into the blender.
- Place the lid on the blender.
- Remove the center cap and set aside.
- Fold a clean and dry dish towel and hold it over the hole’s opening, covering it completely. This allows steam to escape
- Turn the blender on at the lowest speed, keeping the towel over the opening, and slowly ramp up the speed until the soup reaches the desired texture.
- Turn off the blender, taste for seasoning and texture. Adjust as needed.
How to thicken soup without flour or milk
The best thing about this roasted cauliflower soup is that you don’t have to thicken it using anything other than the cauliflower and a blender. Cauliflower is rich in pectin which is a natural thickener. Think apples in applesauce or what helps jam become jam.
Technique tip: you can use other pectin rich veggies like potatoes or carrots to thicken soup in the same way.
One more win for the leftovers!
For a crowd: Serve in shot glasses as an appetizer at a party sprinkled with chili powder and lemon zest.
For a few: Make as is and freeze the rest. See the recipe for freezing tips.
Made this recipe?
I’d love it if you’d share your review and leave a star rating and comment!
Roasted Cauliflower Soup with Lemon
- 1 head cauliflower, trimmed and cut into medium-sized florets
- 1 T oil, I use olive or avocado
- ½ onion diced, small
- 2 cloves garlic, chopped – or 2 tsp bottled garlic
- 1 tsp umami mushroom powder, Trader Joe's
- 1/4-1/2 tsp crushed red pepper
- 1 tsp salt
- ½ tsp black pepper
- 3 cups vegetable broth, can substitute chicken or mushroom broth
- ½ lemon, zested first, then juiced to 2 T
- Preheat oven to 375°
- Add cauliflower to a sheet pan and roast in the oven for 20 minutes until browned.
- Remove from the oven and set aside.
- Meanwhile, heat oil in a 4 qt soup or saucepan and saute onion for 5 minutes until golden.
- Add garlic the last minute of cooking the onions, stirring the whole time. Season lightly with salt and pepper. p.s. don't burn or over-brown the garlic.
- To the soup pan, add the roasted cauliflower, umami powder and crushed red pepper along with salt and pepper. Stir to incorporate for about 1 minute.
- Add chicken broth, lemon zest and the 2 T of lemon juice.
- Simmer over low heat for 10 minutes or so.
- Remove from heat and pour the contents of the pan into a blender.
- Put the lid on the blender and REMOVE MIDDLE INSERT OF THE LID leaving the hole open.
- Place a folded dish towel over the blender hole opening to allow steam to escape.
- Turn the blender on low and slowly ramp up to medium-high speed stopping the blender as needed to scrape the sides or push down the ingredients.
- Blend for about 1-2 minutes until you can a super-smooth texture. Of course, if you like bits of cauliflower, stop the blender sooner.
- Taste and correct for seasoning and/or texture by adding additional broth, if needed.
- Pour into a serving tureen or bowls.
- You can forego using roasted cauliflower if you want to save some time and then cook the cauliflower in the broth until soft which should take about 15 minutes.
- Thin the soup with additional broth, if needed.
About Lori Murphy
Lori has over 30 years in the food industry as a marketing strategist, culinary instructor and chef for three kids with discerning palates. As the chief content creator at Josie + Nina, Lori is dedicated to helping home cooks create food memories through fresh ingredients and Italian flavors.