Looking for a cauliflower blue cheese soup? This one is rich, velvety and full of flavor. Cauliflower and onion are roasted until golden, blended with stock until silky smooth, then topped with crispy bacon and crumbled blue cheese. It’s low carb, made with just 5 ingredients, and on the table in about 30 minutes.
OK, so full disclosure… my Irishman wasn’t a huge fan of this roast cauli soup.
He actually thought the blue cheese ruined it. However, I really loved it.
I could see that the strong Stilton I used was pretty full on. And not for everyone.
So I’d better warn you… unless you’re a massive blue cheese fan like me, you’d best either use a mild, creamy blue (like Castello blue or a creamy gorgonzola) or replace it with Parmesan.
Parmesan and bacon are always excellent friends.
Does Blue Cheese Go with Cauliflower?
Absolutely! It’s a classic pairing, just like cauliflower cheese. Cauliflower is mild, nutty and slightly sweet, which balances the sharp, salty tang of blue cheese beautifully. Roasting the cauliflower first adds caramelized, toasty flavors that make the combination even better.
Why Roast the Cauliflower?
Most cauliflower soup recipes boil the cauliflower, which can make it taste a bit flat and watery. Roasting at a high heat browns the florets and onion, adding deep, sweet, nutty flavor. It’s the secret to a cauliflower soup that tastes rich without needing cream.
Ingredients
- Cauliflower – one head, chopped into bite-sized florets. The stem is fine to use too.
- Onion – roasted with the cauliflower for sweetness.
- Bacon – for a crispy, smoky topping.
- Stock – chicken or vegetable.
- Blue cheese – or Parmesan if you prefer something milder.
- Extra virgin olive oil, salt and black pepper – for roasting and seasoning.
Which Blue Cheese Is Best for Soup?
- Stilton – the famous English blue. Strong, crumbly and tangy. For true blue cheese lovers.
- Gorgonzola – Italian blue. Gorgonzola dolce is soft, creamy and mild.
- Roquefort – French sheep’s milk blue. Sharp and salty, and one of the most famous blue cheeses in the world.
- Danish blue or Castello – creamy and milder, so a good starting point.
See my blue cheese substitutes if you don’t have any.
How to Make Cauliflower Blue Cheese Soup
Roast the cauliflower florets and sliced onion in a very hot oven until tender and golden. Meanwhile, cook the bacon in a pot over medium-high heat until crispy, then remove it and add the stock to the pot. Tip the roasted veg into the stock, simmer briefly, then blend until smooth. Top with bacon and crumbled blue cheese. Full recipe below.
Roast Cauliflower Soup with Bacon & Blue Cheese
Ingredients
- 1 head cauliflower (about 2 lb / 900g) chopped into bite-sized florets
- 1 onion halved lengthwise and sliced into half-moons
- 4-6 slices bacon chopped
- 2 1/2 cups chicken or vegetable stock
- 1 handful crumbled blue cheese or shaved Parmesan
Instructions
-
Preheat your oven to 480°F (250°C) while you chop the cauliflower and onion. Place the veg on a large rimmed baking sheet (the less crowded, the quicker they'll cook). Toss with a little oil, season generously with salt and roast for 15 minutes.
-
Meanwhile, cook the bacon in a medium saucepan with a little oil over medium-high heat until well browned and starting to crisp. Remove the bacon and drain on paper towel. Add the stock to the pot and bring to a simmer.
-
When the timer is up, stir the cauliflower and onion and roast for another 5-10 minutes or until tender and starting to brown.
-
Tip the roasted cauliflower and onion into the stock and bring back to a simmer. Remove from the heat and blend with a stick blender until as smooth or chunky as you like. Taste and season with salt, remembering the bacon and cheese will add extra salt. If it's too thick, add a little water.
-
Divide between two bowls and top with the crispy bacon and cheese.
Recipe Video
WINE MATCH: A buttery Chardonnay or a gutsy Cabernet. If you’re in Australia, try to get a Margaret River or Coonawarra Cab.
Variations & Substitutions
short on time – skip the roasting and simmer the onion and cauliflower in the stock, covered, until tender, about 15 minutes. Cook the bacon in a separate pan while the cauli is simmering. Don’t forget to tip the bacon fat into the soup before blending – it adds a lovely smoky flavor.
vegetarian – replace the bacon with extra cheese, smoked almonds, smoked tofu, sun-dried tomatoes or roasted red peppers. Use vegetable stock.
dairy-free – replace the cheese with extra bacon.
cauliflower cheese soup – stir 1 cup grated sharp cheddar into the blended soup for a cheesy, cauliflower cheese-style soup. Or try my Easy Cauliflower Cheese.
different veg – these flavors are amazing with butternut squash, pumpkin, sweet potato, rutabaga or turnip. Potato will work as well – just be careful when blending so you don’t end up with a gluey mess.
more substantial (carb lovers) – crusty bread and butter.
more substantial (low carb) – extra bacon, extra cheese, or serve with toasted walnuts or almonds. Or stir some salted butter into the soup.
no bacon – see the vegetarian options, or replace with ham or chorizo.
no stock – use water, or water with a few tablespoons of tomato paste for richness and intensity.
How to Thicken Cauliflower Soup
- Use less stock – you can always add more liquid, but you can’t take it away. Start with less and add water as you blend.
- Simmer it down – simmer uncovered for a few minutes to reduce.
- Blend in the cheese – stir some of the blue cheese or Parmesan into the soup before serving.
- Add more cauliflower – a few extra florets make it thicker and creamier.
- Add butter or cream – for a richer, silkier soup.
Is Cauliflower Soup Good for Keto?
Yes! Cauliflower is one of the lowest carb vegetables, and with bacon and blue cheese, this soup is naturally keto-friendly. Just keep an eye on the onion if you’re very strict, or use half the amount.
What to Serve with Cauliflower Soup
Crusty bread and butter is hard to beat. For a lighter meal, serve with a simple green salad. Or add a crunchy topping of toasted breadcrumbs, walnuts or almonds.
Prepare Ahead
Yes! Cook as per the recipe, but keep the bacon and blue cheese separate. The soup will keep in the fridge for 3-4 days, or can be frozen for up to 3 months. To serve, bring back to a simmer and top with the bacon and cheese.
Waste Avoidance Strategy
cauliflower – will keep in a plastic bag in the fridge for a week or two. To keep it longer, chop into florets and freeze.
onion – will keep in the pantry for months. Best in a dark corner in a brown paper bag.
bacon – freeze it.
chicken or vegetable stock – keep unopened in the pantry.
blue cheese – unopened, pre-packaged blue cheese can keep for weeks. Once opened, wrap well and use within a week or two, or freeze.
Parmesan – wrap in waxed paper or parchment paper and store in the fridge in an airtight container. It will keep for months.
More 5-Ingredient Cauliflower Recipes
- Easy Cauliflower Cheese
- Turkish Cauliflower & Yogurt Soup
- 1-Ingredient Whole Roast Cauliflower
- Chunky Roast Cauliflower Chorizo
- One Tray Chicken & Broccoli with Blue Cheese Dressing
In your corner,
Jules from Stonesoup xx
(Your favourite Australian Food Scientist)
See my bio
I was so excited when I saw this yesterday, knowing I had all the ingredients on hand. This was so good Jules! Easy to prepare and a yummy combo of flavors.
Thanks again.
Oh yay Mary!
So glad you enjoyed it :)
I love how your recipes always give me something to do with my local farm delivery box. This week, a rutabega. This roasted rutabega soup is so yummy. I had aged gouda, so that’s what’s on it, with bacon. Thanks so much!
oh yum Murphy :)