Grant Achatz/ Food & Wine

I NGREDIENTS

1 tablespoon unsalted butter

2 tablespoons extra-virgin olive oil

1 small onion, finely chopped

1 garlic clove, thinly sliced

Kosher salt

Freshly ground black pepper

1 1/2 pounds zucchini, halved lengthwise and sliced 1/4-inch thick

2/3 cup vegetable stock or low-sodium broth

1 1/2 cups water

Raw zucchini, julienned for garnish

PREPARATION

In a large saucepan, melt the butter in the olive oil. Add the onion and garlic, season with salt and pepper, and cook over moderately low heat, stirring frequently, until softened, 7 to 8 minutes.

Add the zucchini and cook, stirring frequently, until softened, about 10 minutes. Add the stock and 1 1/2 cups of water and bring to a simmer; cook until the zucchini is very soft, about 10 minutes.

Working in two batches, puree the soup in a blender until it's silky-smooth.

Return the soup to the saucepan and season with salt and pepper. Serve it either hot or chilled, garnished with julienned zucchini.