This creamy cauliflower and leek soup is cozy, silky, and ready in about 40 minutes—no heavy cream required. You’ll sweat sweet leeks, simmer tender cauliflower, then blend it ultra-smooth for a restaurant-worthy bowl. I’ve tested this twice (immersion blender and high-speed blender) and dialed in the timing so you get consistent, velvety results with easy dairy-free and gluten-free options.
If you want a weeknight winner that tastes like it simmered all day, this is it. The mild sweetness of leeks plus buttery-soft cauliflower creates a naturally creamy base, so you can go light on dairy—or skip it entirely. I prefer a small Yukon gold potato for body and a splash of milk (or cashew milk) to finish. As a recipe developer, I focused on a five-step flow, crystal-clear swaps, and foolproof thickness control so your creamy cauliflower and leek soup comes out perfect every time.
At a Glance
- Servings: 6
- Prep Time: 15 minutes
- Cook Time: 25 minutes
- Total Time: 40 minutes
- Difficulty: Easy
- Estimated Cost: $8–$12 (US)
Ingredients
- 2 Tbsp olive oil (30 ml)
- 2 large leeks, white and light green parts only, thinly sliced (about 12 oz / 340 g)
- 2 cloves garlic, minced
- 1 large head cauliflower, cored and cut into florets (about 2 lb / 900 g)
- 1 medium Yukon gold potato, peeled and diced (about 8 oz / 225 g; optional for extra body)
- 4 cups low-sodium vegetable broth (960 ml) (or chicken broth)
- 1 tsp kosher salt, plus more to taste
- 1/2 tsp black pepper
- 1 tsp fresh thyme leaves (or 1/2 tsp dried)
- 1 bay leaf
- 1–2 tsp fresh lemon juice, to finish
- Optional creamy finish: 1 cup milk or half-and-half (240 ml) or 1 cup unsweetened cashew or oat milk (240 ml)
For serving (optional): chopped chives, drizzle of olive oil, gluten-free croutons, crispy chickpeas, reserved roasted cauliflower florets
| Need | Swap | Notes |
|---|---|---|
| Dairy-free | Use cashew milk, oat milk, or 1/2 cup (75 g) soaked cashews blended with 1 cup (240 ml) hot broth | Naturally silky without cream; no coconut flavor. |
| Gluten-free | Use certified GF broth and GF croutons (or crispy chickpeas) | Soup base is naturally GF. |
| Extra protein (vegetarian/vegan) | Add 1 can (15 oz / 425 g) drained white beans | Blend in Step 3 for creaminess and protein. |
| No potato | Increase cauliflower by 8 oz / 225 g | Keeps it light; still velvety. |
| Chicken flavor | Use chicken broth | Still alcohol-free and pork-free. |
Step-by-Step Instructions (Creamy Cauliflower and Leek Soup)
- Sweat the leeks: Warm olive oil in a large pot over medium heat. Add leeks and a pinch of salt. Cook 6–8 minutes, stirring, until soft and sweet but not browned. Stir in garlic for 30 seconds.
- Simmer the veg: Add cauliflower, potato, thyme, bay leaf, salt, pepper, and broth. Bring to a boil, then reduce to a gentle simmer. Cover and cook 12–15 minutes, until cauliflower and potato are very tender.
- Blend smooth: Remove bay leaf. Blend with an immersion blender until silky (or carefully transfer to a high-speed blender in batches; vent the lid).
- Make it creamy: Stir in milk/half-and-half or dairy-free milk. If using beans, blend again until glossy. Warm gently 1–2 minutes—do not boil.
- Finish & serve: Stir in lemon juice. Taste and adjust salt/pepper. Ladle into bowls and top with chives, olive oil, and crunchy toppings.
Pro Tips & Variations
- Thickness control: Too thick? Add warm broth or water 2 Tbsp at a time. Too thin? Simmer uncovered 3–5 minutes or blend in a few extra cauliflower florets or 1 Tbsp instant mashed potato flakes.
- Ultra-smooth texture: High-speed blender = glassy finish. Work in small batches and keep steam vented.
- Roasted depth: Roast 2 cups of the cauliflower florets at 425°F (220°C) with a little oil and salt until golden (20–25 minutes) and blend half into the soup; use the rest as a topper.
- Curry twist: Add 2 tsp mild curry powder with the leeks in Step 1; finish with coconut-free cashew milk.
- Vegan cheesy note: Stir in 2–3 Tbsp nutritional yeast at the end.
- Make-ahead: Cook through Step 3, cool, and refrigerate up to 4 days. Finish with milk and lemon just before serving for freshest flavor.
Serving Suggestions
- Add chives, a drizzle of olive oil, and gluten-free croutons.
- Top with crispy chickpeas or roasted cauliflower for crunch.
- Pair with a simple green salad or no-knead bread (GF if needed).
Storage & Reheating
- Fridge: Up to 4 days in airtight containers. Cool quickly; store within 2 hours.
- Freezer: 2–3 months. For best texture, freeze before adding dairy; stir in milk after reheating.
- Reheat: Warm gently on the stovetop over low heat, stirring. Avoid boiling after dairy is added to prevent separation.
Troubleshooting
- Bitter flavor: Use only white/light green leek parts; rinse thoroughly to remove grit. Add 1–2 tsp lemon juice to balance.
- Grainy soup: Blend longer or add a splash of milk/cashew milk and re-blend.
- Too bland: Increase salt gradually and finish with lemon and fresh chives.
- Color looks dull: Don’t overcook; brighten with lemon and green toppings.
FAQs
Q1: Can I make creamy cauliflower and leek soup without potato?
A1: Yes. Replace the potato with 8 oz (225 g) more cauliflower or blend in 1/2 cup (75 g) soaked cashews for body.
Q2: Do I need to roast the cauliflower first?
A2: No. The base is flavorful as-is. But roasting some florets (425°F/220°C for 20–25 minutes) adds a deeper, nutty note.
Q3: Can I use frozen cauliflower?
A3: Absolutely. Add it straight from frozen and simmer until tender; texture stays smooth after blending.
Q4: What’s the best way to blend hot soup safely?
A4: Immersion blender right in the pot, or small batches in a vented high-speed blender. Cover the vent with a towel and start low.
Q5: How do I make it fully vegan?
A5: Use vegetable broth and finish with cashew or oat milk; add white beans for protein and creaminess.
Nutrition (per serving)
Approximate, for 6 servings with milk and potato.
Calories: 160; Protein: 6 g; Carbs: 20 g; Fat: 7 g