1 large or 2 medium butternut squash (about 4 1/2 pounds), or 3 pounds peeled and cubed
2 medium onions (can use leeks as well)
3 cloves garlic, optional
3 tablespoons unsalted butter, or vegetable oil
1/2 teaspoon fine sea salt, plus more to taste
8 cups chicken or vegetable broth
Chives and Pepitas for garnish, if desired
Halve, seed, peel, and cube the butternut squash. Set aside.
Halve, peel, and chop onion. Mince the garlic, if you’re using it.
Heat a large pot over medium-high heat. Add the butter or oil and the chopped onion. Sprinkle with 1/2 teaspoon salt. Cook, stirring occasionally, until the onion is soft, about 3 minutes.
Add the garlic and cook until fragrant, about 1 minute.
Add the squash and the broth. Bring to a boil. Cover, reduce heat to a simmer, and cook until the squash is tender, about 20 minutes.
Transfer small batches to a blender. Hold a kitchen towel over the top (to prevent burns) and whirl until completely and utterly smooth, 2 to 3 minutes per batch.
Return the soup to the pot and add more salt to taste. Garnish as desired.