Preheat your oven to 425°F (220°C) and line a baking sheet with parchment paper. Cut the butternut squash in half lengthwise and remove the seeds. Reserve the seeds for later use. Remove the skin from the onion and cut it into four large pieces. Slice the top off a whole head of garlic, drizzle with about a teaspoon of olive oil, and wrap it in a piece of foil. Arrange the squash halves (cut side up), onion pieces, and the wrapped garlic on the prepared baking sheet. Drizzle the squash and onion with about 2 tablespoons olive oil, and sprinkle with sea salt, cracked black pepper, chopped fresh sage, and thyme leaves. I like to make sure all the veggies are well coated for maximum flavor.

Place the prepared baking sheet in the preheated oven and roast the vegetables for about 45 minutes, or until the squash is easily pierced with a fork and the onion is soft and caramelized. Once done, carefully remove the baking sheet from the oven and allow the vegetables to cool slightly so they are easier to handle.

Meanwhile, rinse the reserved butternut squash seeds in a colander to remove any attached pulp, then pat them dry thoroughly using a towel. Place the cleaned seeds in a bowl, add 1 tablespoon olive oil and a pinch of salt, and toss to coat well. Spread the seeds onto a separate baking sheet and roast them in the oven at 350°F (176°C) for 15-20 minutes, stirring halfway through. Don’t worry if you hear the seeds pop—it’s normal! For extra crunch, I sometimes bake them for an extra couple of minutes, but watch closely to prevent burning.

Once the roasted vegetables are cool enough to handle, scoop the flesh from the butternut squash, squeeze out the roasted garlic cloves from the foil, and add them together with the roasted onions into a large stockpot. Pour in the vegetable broth and use an immersion blender to puree everything until smooth and creamy. Heat the soup over low heat until fully warmed through. Stir in the heavy cream. Taste and adjust seasoning as needed. I like to add a bit more salt or a dash of black pepper at this stage to enhance the flavors.

Ladle the hot soup into bowls. Top each serving with a handful of roasted butternut squash seeds from Step 3 and some homemade croutons for crunch. Enjoy your delicious homemade soup!