Roasted Butternut Squash Soup

Roasted butternut squash soup is a rich creamy soup, bursting with the flavors of fall, fresh thyme and topped with toasted cashews. The first time I tasted this roasted butternut squash soup recipe was Aspen, Christmas, 1991, at a restaurant called The Attic.

It was the same restaurant we would eat every Christmas. But this night, as part of the prix fixe menu, we had butternut squash soup with toasted cashews as a starter. I could have stopped there, skipped the Prime Rib, the Yorkshire Pudding and the English Trifle and just had more soup. (This post was originally published on October 15th, 2012 )

I still remember the mouth feel and creamy texture of that soup. The crunch of the cashews, and just a hint of nutmeg. I asked the waiter, who asked the chef, for the recipe. The young chef, flattered, came out to our table with a yellow legal pad and apologized for the vague ingredients and lack of directions, “My recipe serves 200”, he said. “That’s OK,” I told him. “I’ll figure it out if you give me the ingredients.”

I recreated that soup, and now it’s on my Autumn/Winter soup list every year since. It’s rich, it’s elegant, and perfect for Thanksgiving or as part of an autumn dinner party.

Ingredients for roasted butternut squash soup

I’ve adapted the original recipe, which was thickened with a roux (flour and butter). When the amount of liquid is reduced in ratio to the squash, it will thicken fine on its own. This also keeps it gluten free and lower in carbs. The original recipe also used heavy cream, which gives it richness and body…but I add just enough cream to bring it to the right consistency.

• 1 butternut squash about 1 1/2 pounds
• 2 cups chicken stock (or vegetable stock for vegetarian/vegan)
• 1 shallot minced
• 2 garlic cloves, minced (about 1 teaspoon)
• 1 Tablespoons butter
• 2 Tablespoons extra virgin olive oil or avocado oil
• 1 sprig of fresh thyme
• 1 bay leaf
• 1/8 teaspoon fresh nutmeg
• 1 teaspoon Kosher salt (to taste)
• 1/2 teaspoon white pepper (to taste)

Optional

• 1/4 cup heavy cream use to thin to desired consistency as needed
• 1/8 cup raw cashews chopped and toasted for garnish

How to roast butternut squash

Skip this step if you are using pre-packaged cubed butternut squash.

Two methods to prepare butternut squash for soup

The first method is halve the squash and bake it until almost done. The second method is to peel the squash first, halve it, scoop out the seeds, cube it and then roast it. The following directions are for the first method.

• Preheat oven to 350 degrees F.
• Halve squash and place cut side up in a single layer on a large sheet pan or dish with 1/2″ of water. bake uncovered for about 45 minutes. Squash won’t be fully cooked, but slightly tender. Cool.
• Using a vegetable peeler, peel of outer skin and scrape inside to remove seeds and stringy fibers. Cut into cubes. Should yield about 6 cups.

Partially cooking the squash before peeling makes the job much easier.

The second method for roasting butternut squash

• Preheat oven to 375 degrees F. Toss butternut squash cubes with olive oil and roast for 15-20 minutes or until butternut squash is partially cooked, but not soft. The squash will finishing cooking on the stovetop.

How to make butternut squash soup

• In a Dutch oven or large soup pot melt butter and olive oil over medium-low heat until hot and shimmering. 
• Add butter, and shallots and stir, for a minute or two, then add garlic and cook for another minute.
• Next, add squash and broth and bring to a boil. Add thyme and bay leaf, reduce heat and cover. 
  

• Simmer on low about 20-25 minutes until squash is tender. Remove bay leaf and thyme bundle,
• Puree soup using an immersion blender, food processor, or high-powered blender, until smooth.
• Return soup to pot, add half and half or cream to thin to desired consistency. Finish with toasted, chopped cashews and a drizzle of cream.
• To toast the cashews, shake in a small frying pan over medium heat until light and golden.

​Store any leftover soup in an airtight container in the refrigerator for up to 4 days.

How to make this a vegan or vegetarian soup

The original recipe using chicken broth. To make it vegetarian, substitute vegetable broth. To make it vegan, swap the butter for more olive oil, and use vegetable broth. Skip thinning with cream, add more vegetable broth, or your favorite dairy substitute like coconut milk until it reaches the right consistency.

Safety Tip!

If using a blender to puree the soup, be careful not to fill the blender more than half way full. Cover lid with a tea towel and hold the lid down while blending so any hot liquid doesn’t explode. 

Garnishing the soup

This is totally optional but makes for a pretty presentation.

Making the “swirl”

You’ll need a squeeze bottle like this one, or a small jug with a fine spout. You’ll want to make the lines fairly thin.

Make a spiral, starting in the center.

Use a sharp object, like a skewer or toothpick and drag it through the cream.

Go first one direction, then the other until the desired look is achieved.

I think it looks like a fall leaf!

Top with toasted cashews and garnish with chopped thyme.

Here are more of my favorite recipes for autumn.

The following dishes are not only hearty for fall, they’re vegetarian.

Butternut Squash Lasgana

Delicata Squash with Sage

Papa al Pomodoro (Italian Bread Soup)

Tuscan White Bean Soup