01 - Heat 1 tablespoon olive oil and 1 tablespoon butter in a large skillet over medium heat. Add diced butternut squash and sliced Brussels sprouts. Cook for 7 to 8 minutes until softened and lightly browned. Remove from skillet and set aside.
02 - Add remaining olive oil and butter to the skillet. Sauté the cleaned and sliced leek along with minced garlic for 2 to 3 minutes until fragrant and translucent.
03 - Stir in the riced cauliflower and cook for 3 to 4 minutes, stirring occasionally to prevent sticking.
04 - Gradually add warmed vegetable broth, ½ cup at a time, allowing each portion to absorb completely before adding more. Continue cooking for approximately 10 minutes until cauliflower is tender and most liquid has evaporated.
05 - Return sautéed butternut squash and Brussels sprouts to the skillet. Stir in baby spinach, dried thyme, ground nutmeg, salt, and black pepper. Cook for 2 minutes until spinach is wilted.
06 - Reduce heat to low, then stir in grated Parmesan cheese, heavy cream, and lemon zest. Gently cook for an additional 2 minutes until the mixture is creamy and well combined. Adjust seasoning if needed.
07 - Serve warm, garnished with extra Parmesan and a drizzle of olive oil if preferred.