1. Cook pasta according to package. In a large skillet over medium heat, cook bacon for approximately 5 minutes or until desired crispness. Add onion and saute until onion is tender (5 to 6 minutes). Stir in chicken stock and sage. Simmer for 1 to 2 minutes.
2. Add spinach and cook until spinach wilts. Salt and pepper to taste.
3. Toss linguine with sauce and serve sprinkled with Parmesan.