Quick Recipe Version (TL;DR)
Quick Ingredients
- 2 tbsp olive oil
- 1 tbsp unsalted butter
- 1 medium yellow onion, chopped
- 4 cloves garlic, minced
- 1 1/2 lb zucchini (about 3 medium), sliced
- 1 medium potato (about 8 oz), peeled and diced
- 4 cups low-sodium vegetable or chicken broth
- 1/2 tsp kosher salt, plus more to taste
- 1/4 tsp black pepper
- 1/8 tsp red pepper flakes (optional)
- 1/2 cup heavy cream
- 1 tbsp fresh lemon juice (optional)
- 1/2 cup fresh basil leaves, plus extra for garnish
- Optional: extra virgin olive oil, grated Parmesan, crusty bread
Do This
- 1. Sauté onion in olive oil and butter over medium heat until soft, 5–7 minutes.
- 2. Stir in garlic, cook 30–60 seconds, then add zucchini and potato; cook 5 minutes.
- 3. Pour in broth, add salt, pepper, and red pepper flakes; bring to a gentle simmer.
- 4. Simmer on low (about 180–190°F / 80–90°C) until potatoes are very tender, 12–15 minutes.
- 5. Turn off heat; stir in cream and basil leaves.
- 6. Blend until completely smooth (immersion or regular blender), then adjust thickness with a splash of broth or water.
- 7. Taste and finish with lemon juice, more salt and pepper; garnish with basil, olive oil, and Parmesan to serve.
Why You’ll Love This Recipe
- It turns simple, inexpensive vegetables into a silky, restaurant-worthy soup.
- Blends up beautifully smooth and creamy, with only a modest amount of cream.
- Easy enough for a weeknight, elegant enough for a dinner party starter.
- Flexible: can be made vegetarian, lighter, or richer with a few quick tweaks.
Grocery List
- Produce: Zucchini, yellow onion, garlic, potato, fresh basil, lemon (optional).
- Dairy: Heavy cream, unsalted butter, Parmesan cheese (optional for serving).
- Pantry: Olive oil, low-sodium vegetable or chicken broth, kosher salt, black pepper, red pepper flakes (optional), crusty bread or baguette (optional).
Full Ingredients
For the Creamy Zucchini and Garlic Soup
- 2 tbsp olive oil (plus more for drizzling when serving, if desired)
- 1 tbsp unsalted butter
- 1 medium yellow onion (about 6 oz), finely chopped
- 4 cloves garlic, minced
- 1 1/2 lb zucchini (about 3 medium), ends trimmed, sliced into 1/4-inch half-moons
- 1 medium potato (about 8 oz), such as Yukon Gold or russet, peeled and cut into 1/2-inch cubes
- 4 cups (960 ml) low-sodium vegetable or chicken broth
- 1/2 tsp kosher salt, plus more to taste
- 1/4 tsp freshly ground black pepper, plus more to taste
- 1/8 tsp crushed red pepper flakes (optional, for gentle heat)
- 1/2 cup (120 ml) heavy cream
- 1 tbsp freshly squeezed lemon juice (optional but brightens the flavor)
- 1/2 cup loosely packed fresh basil leaves (about a small handful)
For Serving
- Fresh basil leaves, thinly sliced or torn
- Extra virgin olive oil, for drizzling (optional)
- Freshly grated Parmesan cheese (optional)
- Crusty bread or toasted baguette slices (optional)
Step-by-Step Instructions
Step 1: Prep the vegetables
Wash and dry the zucchini, then trim off the ends. Slice each zucchini lengthwise, then cut into 1/4-inch half-moons so they cook quickly and blend smoothly. Peel the potato and cut it into 1/2-inch cubes; this helps it soften at the same rate as the zucchini. Peel and finely chop the onion, and mince the garlic cloves. Rinse the basil leaves, pat them dry, and set them aside for later.
Step 2: Sauté the onion and garlic
In a large, heavy-bottomed pot (such as a Dutch oven), heat the olive oil and butter over medium heat until the butter is melted and foamy. Add the chopped onion and a small pinch of salt. Cook, stirring occasionally, until the onion is soft and translucent but not browned, about 5–7 minutes.
Add the minced garlic and cook for 30–60 seconds, stirring frequently, just until fragrant. Avoid browning the garlic, which can make the soup taste bitter.
Step 3: Add zucchini and potatoes
Stir in the sliced zucchini and the diced potato. Sprinkle with the 1/2 teaspoon kosher salt, 1/4 teaspoon black pepper, and the crushed red pepper flakes if using. Cook, stirring occasionally, for about 5 minutes. The zucchini should start to soften and release some of its juices; this builds flavor before you add the broth.
Step 4: Add broth and simmer until tender
Pour in the broth, scraping up any bits stuck to the bottom of the pot. Increase the heat to medium-high and bring the soup just to a gentle boil. Once it reaches a boil, immediately reduce the heat to low so the soup is at a steady simmer, about 180–190°F (80–90°C), with small, lazy bubbles breaking the surface.
Cover the pot partially with a lid and simmer until the potatoes are very tender and easily crushed with a spoon, 12–15 minutes. This ensures the soup will blend velvety smooth.
Step 5: Stir in cream and basil
Turn off the heat. Stir in the heavy cream until fully combined. Add the 1/2 cup fresh basil leaves, pressing them down into the hot liquid so they wilt. Let the soup sit for 2–3 minutes off the heat; this brief rest lets the flavors meld and softens the basil so it blends in easily.
Step 6: Blend the soup smooth
For the safest and easiest method, use an immersion blender directly in the pot to blend the soup until completely smooth and creamy, 2–4 minutes. Move the blender around the pot and tilt it slightly to catch any remaining chunks.
If using a countertop blender, let the soup cool slightly first. Transfer it in batches, filling the blender no more than halfway, and vent the lid so steam can escape while holding a kitchen towel over the top. Blend until silky smooth, then return the soup to the pot.
If the soup is thicker than you like, stir in an extra splash of broth or water until it reaches your preferred consistency, then gently rewarm over low heat if needed.
Step 7: Taste, adjust, and serve
Taste the soup and adjust the seasoning. Add more salt and pepper as needed. If you like a brighter, fresher flavor, stir in the lemon juice a little at a time, tasting as you go. Warm the soup gently over low heat, stirring often, until it is hot but not boiling.
Ladle the soup into warm bowls. Garnish each bowl with a few fresh basil leaves (torn or thinly sliced), a drizzle of good olive oil, and a sprinkle of freshly grated Parmesan, if using. Serve immediately, ideally with crusty bread for dipping.
Pro Tips
- Keep the color vibrant: Do not brown the zucchini or garlic. Gentle sautéing keeps the soup a pretty pale green and preserves the delicate flavor.
- Simmer, do not boil hard: A gentle simmer (not a rolling boil) keeps the flavors soft and prevents the cream from separating later.
- Blend thoroughly: For an ultra-smooth texture, blend longer than you think you need to, then check for any tiny chunks by rubbing a bit of soup between your fingers.
- Adjust thickness at the end: If the soup is too thick, thin with warm broth or water; if too thin, simmer uncovered for a few minutes to reduce slightly.
- Dairy-free option: Swap the heavy cream for full-fat coconut milk or an extra potato plus a drizzle of olive oil for richness.
Variations
- Extra-herby version: In addition to basil, add a small handful of fresh parsley or chives during blending for a more complex herbal flavor.
- Parmesan-rich soup: Simmer a parmesan rind in the soup with the broth, then remove it before blending. Finish with extra grated Parmesan for a deeper savory note.
- Spicy zucchini soup: Increase the crushed red pepper to 1/4 teaspoon and add a pinch of smoked paprika for a gentle, warming heat and subtle smokiness.
Storage & Make-Ahead
Let the soup cool to room temperature, then transfer it to airtight containers. Refrigerate for up to 4 days. Reheat gently on the stove over low to medium-low heat, stirring often, until steaming hot but not boiling. If the soup thickens in the fridge, loosen it with a splash of water or broth while reheating.
For longer storage, freeze the soup (preferably before adding the basil garnish and any Parmesan) in freezer-safe containers for up to 2–3 months. Thaw overnight in the refrigerator before reheating. The texture may thicken slightly after freezing; blend briefly again if needed and adjust with a bit of broth. Always add fresh basil and any cheese garnishes just before serving for the best flavor and color.
Nutrition (per serving)
Approximate values for 1 of 4 servings (without optional Parmesan or bread): about 320 calories; 23 g fat; 23 g carbohydrates; 5 g fiber; 6 g protein; 720 mg sodium (will vary depending on broth and added salt). These numbers are estimates and will change if you adjust the cream, use different broth, or add toppings.
