Bring a large pot of salted water to a boil and cook the cheese tortellini according to package instructions, about 3-5 minutes for fresh or 7-10 minutes for frozen. Drain and reserve a cup of pasta water.

In a large non-stick skillet, heat olive oil over medium heat. Add minced garlic and sliced mushrooms, sautéing for 3-4 minutes until soft and golden.

Pour in heavy cream into the skillet with sautéed mushrooms. Stir well and bring to a gentle simmer for about 2 minutes, allowing it to thicken slightly.

Fold drained tortellini into the creamy sauce, then add fresh spinach and grated Parmesan cheese. Cook for 2 minutes until spinach wilts and cheese melts.

Season with salt and pepper to taste. If the sauce is too thick, stir in a splash of reserved pasta water. Serve immediately.