Heat a large skillet over medium heat and pour in olive oil. Add onion, carrot, and celery, and sauté until softened, about 5-7 minutes.

Increase heat and add ground meat, breaking it apart as it cooks. Brown thoroughly, about 5-7 minutes.

Pour in white wine, scraping the bottom of the pan to release browned bits. Simmer until mostly evaporated, about 3-5 minutes.

Reduce heat to low, stir in milk or cream, and let simmer gently for 30-45 minutes, stirring occasionally.

Add nutmeg, salt, and pepper to taste, and continue stirring until sauce reaches the desired consistency.

Remove from heat and stir in freshly grated Parmesan cheese until melted and creamy.

Serve hot over pasta or use in lasagna or with roasted vegetables.