This healthy cauliflower and broccoli soup is creamy, comforting and packed with vegetables. Ready in under 30 minutes, it's an easy family lunch and can be made with fresh or frozen vegetables.
Soften the onion: Heat 1 tbsp of Olive oil in a large saucepan over a low-medium heat.
Add 1 Onion (diced) and cook gently for 4-5 minutes until softened. Add 2 Garlic cloves (crushed) for the final minute.
Don't rush the onion. Giving it those few minutes to soften adds more flavour than simply boiling everything together.
Add the vegetables: Add 500 g of Cauliflower and 300 g of Broccoli. If you are using the stalks, chop them smaller than the florets so everything becomes tender at roughly the same time.
Season: Season with ¼ tsp of Fine sea salt and ½ tsp of Ground black pepper.
Add the stock: Pour in 700 ml of Vegetable stock and bring everything to a gentle boil, about 5 minutes.
Simmer: Reduce to a simmer, cover and cook for around 12-15 minutes, or until the vegetables are completely tender when pierced with a knife. You don't want hard pieces left before blending, particularly if you want a really smooth soup.
Blend: Remove the pan from the heat and, using an immersion blender, blend until smooth. For a slightly chunkier broccoli and cauliflower soup, you can blend only three-quarters of it and leave a little texture.
Milk & cream: Stir through 300 ml of Skimmed milk and 100 ml of Single cream, if using.
Cheese: gradually add 100 g of Mature cheddar (grated) and stir over a low heat until melted, around 1-2 minutes.
Test: Taste and adjust the seasoning.
Don't vigorously boil the soup once the dairy and cheese have been added, as gentle heat gives you a smoother finish.
Notes
Weigh the vegetables. Broccoli and cauliflower heads vary considerably in size, so using gram weights gives you a much more consistent soup.
Use the stalks. Chop them smaller than the florets so they soften properly.
Start with less stock. You can always thin a thick soup after blending, but fixing a watery soup is harder.
Use mature cheddar. A stronger cheese gives more flavour without needing as much.
Don't boil it after adding the dairy. Heat it gently once the milk, cream and cheese are added.
Use an immersion blender if possible. It's easier and considerably less messy than transferring hot soup to a jug blender.
Taste after adding the cheese. Stock and cheddar can both be salty, so don't add lots of salt at the beginning.