Heat olive oil in a large pot or Dutch oven over medium heat.
Add chopped onion and cook until softened, about 5-7 minutes.
1.5 pounds zucchini
Add minced garlic and cook for another minute until fragrant, being careful not to burn it.
1.5 pounds zucchini
Add the chopped zucchini and vegetable broth to the pot. Bring to a boil, then reduce heat and simmer for 15-20 minutes, or until zucchini is very tender.
1.5 pounds zucchini
Carefully transfer the soup to a blender (or use an immersion blender) and blend until smooth. You may need to do this in batches.
Return the pureed soup to the pot. Stir in the heavy cream, salt, and pepper. Heat gently until warmed through, but do not boil.
1.5 pounds zucchini
Taste and adjust seasoning as needed. Serve hot, garnished with fresh herbs or a swirl of cream if desired.
Notes
For a vegan option, substitute the heavy cream with full-fat coconut milk or a dairy-free creamer. You can also garnish with toasted pumpkin seeds or croutons.