In a large skillet, heat olive oil over medium heat. Sauté onion and garlic for 2 minutes.
Add mushrooms and cook until browned (5–6 minutes).
Stir in orzo and cook for 1 minute, toasting lightly.
Pour in vegetable broth and bring to a simmer. Cook uncovered, stirring occasionally, for 8–10 minutes until orzo is tender and most liquid is absorbed.
Stir in spinach, Parmesan, and cream. Season with salt and pepper.