This 6-ingredient vegan roasted cauliflower soup is rich, creamy and without dairy! Roasted cauliflower is another level of delicious and when you treat simple and cheap ingredients right, you get the best vegan cauliflower soup recipe you’ve ever tasted!
I love me some creamy vegan soups! One of the first recipes I published on the blog is this vegan potato leek soup. That was waaay back when I could still afford to buy cashews.
I now have two new favourite ingredients for adding creaminess to my vegan soups and sauces. The first is unsweetened soy yogurt, which is amazing in this vegan ranch dip, and the second is coconut milk.
A while back I reviewed a cookbook that had a recipe for vegan alfredo sauce. The sauce is made from cauliflower and either cashews or coconut milk. I opted for the coconut milk and was surprised that it didn’t taste at all like coconut. So I decided to expand on that idea and make this epic and flavour-packed vegan roasted cauliflower soup!
How to make vegan roasted cauliflower soup
Instead of just simmering the cauliflower like most vegan cauliflower soup recipes do, I wanted to really bring out the sweetness of the cauliflower by roasting it first.
Roasting vegetables often takes 45 minutes but there are two tricks I use to make this soup quick to prepare and great for a weekday dinner.
First, you don’t need to wait for your oven to fully preheat before putting the pan in. It really doesn’t make a difference if vegetables start roasting in a cooler oven, they come out fully roasted in the end.
So simply cut the core out of the cauliflower, pull or cut the florets into smaller pieces, drizzle over some olive oil and salt and throw that pan in the oven.
Secondly, I roast the cauliflower at a rather high temperature in order to get it finished sooner. Don’t worry, it still comes out tender, sweet and with delicious roasted flavour, even a bit smoky as the small bits will char a little and add even more complexity to the soup.
(Aside: have you ever had a whole cauliflower roasted in a wood-burning oven until nearly charred? I had it at an Israeli restaurant and it was one of the most delicious things I’ve ever put in my mouth).
Just keep an eye on it to ensure that you don’t burn it too much!
While the cauliflower is roasting, you can fry the onion. Another trick to squeezing out as much flavour as possible is to slow cook the onion over low heat.
Normally you cook onions in about 5 minutes but since you have time to spare while the cauliflower roasts, you can slowly soften the onion for 10 – 15 minutes.
Slow cooked onions add a great deal of complexity and richness to the soup. It’s not just me who thinks so, this article from Cook’s Illustrated explains the science behind why it’s always best to slow cook your onions when making soups and sauces!
When everything is just about ready, add your favourite fresh or dried herb. I chose dried thyme but you can experiment with whatever herb or even a pinch of nutmeg or curry powder.
Add some vegetable stock and bring it up to the boil. Now you have two options for blending: either transfer the pot and cauliflower to a blender or toss the cauliflower into the pot and use a stick blender.
Personally, my upright blender makes smoother soups than my stick blender so I prefer that option. Begin blending, carefully and with the lid cracked to allow steam to escape, and when it’s mostly broken down pour in the coconut milk.
I prefer to add the coconut milk to the blender rather than heating it in the pot with the stock because it can sometimes split or get weird when it’s boiled. It shouldn’t cool down your soup too much when adding it but if it does you can always transfer the contents back to your pot and heat for another minute or two.
That’s it! Taste and adjust the seasonings as you see fit and serve. You can use the leftover coconut milk as a garnish drizzled over and whatever other garnishes you like. I especially love this vegan roasted cauliflower soup served with lots of crusty bread on the side for dipping!
Vegan Roasted Cauliflower Soup
- 1 head of cauliflower about 2 pounds / 1 kilo after removing the leaves – $2.99
- 2 tablespoons of olive oil divided – $0.32
- Several pinches of salt to taste – $0.05
- 1 large onion finely diced – $0.24
- 2 cloves of garlic finely diced – $0.16
- 1 teaspoon dried thyme or your favourite herb – $0.09
- 2 ½ cups vegetable stock – $1.13
- 1 cup coconut milk – $2.05
- Optional garnishes: leftover coconut milk chopped fresh thyme, parsley or other herb, croutons, etc.
- Turn on the oven to 450 F / 230 C.
- Remove the core from the cauliflower and pull apart the florets with your hands or cut them with a knife into smaller pieces. Place on a baking tray and drizzle with 1 tablespoon of oil and a pinch of salt. Toss to coat and put the pan in the oven. The oven does not need to be fully preheated when you put the pan in – it will start roasting even as the oven heats up. Roast for 20 minutes or until tender and golden, stirring once. It’s ok if there are a few charred bits, it adds flavour, but keep an eye on it so it doesn’t totally burn.
- Meanwhile, heat 1 tablespoon of oil in a medium (if using a stand blendeor large pot (if using an immersion blendeover medium-low heat.
- Add the onion and a pinch of salt. Allow to slow cook until soft and lightly golden, stirring occasionally, while the cauliflower roasts – about 15 minutes. Slow cooking the onion adds a ton of flavour so lower the heat if it’s browning too quickly.
- When the cauliflower is a few minutes out, add the garlic and thyme to the onion and cook until fragrant and soft.
- Finally, add the stock to the pot and turn the heat to high to bring to a boil.
- If you are using a regular blender, transfer the cauliflower and contents of the pot to the blender. Begin blending with the lid ajar to allow steam to escape. When it’s mostly broken down, add in the coconut milk. The coconut milk should not cook the soup too much but you can always transfer it back to the pot to reheat if necessary.
- If using an immersion blender, add the cauliflower to the pot with the stock and begin blending. When it’s mostly broken down, add in the coconut milk.
- Taste and adjust the seasoning if necessary. Serve with a drizzle of the remaining coconut milk and your choice of garnishes.