01 - Heat olive oil in a large soup pot or Dutch oven over medium heat. Add the Italian sausage, breaking it apart with a wooden spoon, and cook until evenly browned. Transfer the sausage to a plate using a slotted spoon, leaving the rendered fat in the pot.
02 - Add the diced onion, sliced carrots, and sliced celery to the pot. Cook for 5 minutes, stirring occasionally, until the vegetables have softened. Add the minced garlic and cook for 1 minute until fragrant.
03 - Stir in the cubed butternut squash, dried thyme, ground nutmeg, and half of the chopped fresh sage. Season with salt and pepper to taste, then sauté for 2 to 3 minutes to coat the squash in the seasonings.
04 - Pour in the chicken broth and bring to a boil. Reduce the heat to a simmer, cover the pot, and cook for 20 minutes until the butternut squash is fork-tender.
05 - Use an immersion blender to purée part or all of the soup for a creamy, velvety base. For a chunkier consistency, blend only half of the soup.
06 - Return the browned sausage to the pot. Stir in the cheese tortellini and simmer uncovered for 6 to 8 minutes until the tortellini is cooked through and tender.
07 - Stir in the heavy cream and the remaining fresh sage. Heat gently without boiling. Adjust the seasoning with additional salt and pepper if needed, then remove from heat.
08 - In a small mixing bowl, blend the softened cream cheese, ricotta cheese, finely chopped sage, milk, and a pinch of salt and pepper until smooth and creamy.
09 - Ladle the hot soup into serving bowls. Add a generous spoonful of the sage cheese swirl to each bowl and gently swirl it into the soup with a spoon or knife. Garnish with extra fresh sage leaves or cracked black pepper and serve immediately.