Cook jumbo pasta shells or manicotti tubes according to package directions. Prepare a filling by combining cooked, drained spinach with ricotta, mozzarella, grated Parmesan, beaten egg, and seasonings. Spoon filling into shells and arrange in a baking dish with marinara or béchamel sauce.
Top with more sauce and shredded cheese, cover with foil, and bake at 375°F (190°C) for 20–30 minutes until hot and bubbling. Uncover and bake a few minutes more for a golden top.
Variations:
This is a satisfying, family-friendly main that freezes well.