Chef John's Roasted Butternut Squash Soup

Preheat oven to 400 degrees F (200 degrees C).

Drizzle olive oil into large roasting pan. Add onion, carrots, garlic cloves, and a pinch of salt. Toss until coated in oil. Place squash halves flesh side up on the chopped vegetables. Sprinkle squash with additional salt.

Roast in preheated oven until squash is tender and easily pierced with the tip of a knife, about 1 hour. Allow vegetables to cool a bit.

Melt butter over medium heat. Butter will foam, and start to turn a golden brown. Reduce heat to low. When butter turns from golden to a light, nutty brown, remove pan from heat and immediately add sage leaves. Stir to infuse the butter with sage.

Scoop out squash flesh and place in roasting pan with roasted chopped vegetables. Transfer mixture into large stock pot. Stir in chicken broth, brown sage butter, and maple syrup. Place pot over high heat and bring to a simmer. Reduce heat to low; slowly simmer to blend flavors, 45 to 60 minutes. Remove from heat.

Blend until very smooth with an immersion blender, 3 or 4 minutes. Pass mixture through a strainer to remove any remaining fibrous bits.

If soup seems too thick, add a few tablespoons of water or chicken broth. Stir in apple cider vinegar, a pinch of salt (or to taste), and cayenne pepper. Garnish servings of soup with a dollop of creme fraiche and chopped chives.