Preheat your oven to 400°F (205°C). Place the halved butternut squash cut-side up on a rimmed baking sheet. Drizzle with 1 tablespoon of olive oil and season with salt and pepper.

Flip the squash cut-side down and roast for 45 to 50 minutes, until the flesh is completely tender when pierced with a fork and the cut surface is deeply golden and caramelized. Remove from oven and let cool for 10 minutes, then scoop the flesh out of the skin and set aside.

In a large heavy-bottomed pot or Dutch oven, heat the remaining 1 tablespoon of olive oil over medium heat. Add the chopped onion and cook, stirring occasionally, for 6 to 8 minutes until softened and translucent.

Add the smashed garlic cloves and cook for another 1 to 2 minutes until fragrant, being careful not to let it brown.

Add the roasted squash flesh to the pot along with the broth. Stir to combine and bring to a gentle simmer over medium heat. Simmer for 10 minutes to let the flavors meld.

Using an immersion blender, blend the soup directly in the pot until completely smooth and silky. Alternatively, transfer in batches to a blender (never more than half full), vent the lid, and blend until silky. Return to the pot.

Stir in the heavy cream and freshly grated nutmeg. Taste and adjust seasoning with additional salt, pepper, or a small squeeze of lemon juice to brighten. Keep warm on low heat while you prepare the garnish.

In a small skillet, melt the butter over medium heat. Once it begins to foam, add the sage leaves in a single layer. Fry for 30 to 60 seconds per side until the leaves are crisp and the butter is beginning to turn golden brown and fragrant. Remove the sage to a paper towel-lined plate immediately.

Ladle the soup into bowls. Swirl in a small amount of additional cream, top with 2 to 3 crispy sage leaves, a sprinkle of toasted pepitas if using, and a crack of fresh black pepper. Serve immediately.