1. Boil a large pot of water, and boil your shells until al dente.
2. Mix ricotta, egg white, garlic powder, salt, pepper, and 1/2 cup mozzarella in a medium sized bowl.
3. Lay about 4 stacked paper towels flat on your counter. Spread the thawed spinach out on these towels, and top with about 3 additional paper towels. Press hard to remove all the water from the spinach. This is very important. Otherwise your pasta will be watery.
4. Mix Spinach into ricotta mixture until everything is well incorporated.
5. Spread about 3/4 cup of marinara sauce on the bottom of an 8X13 baking pan.
6. Carefully stuff each shell with about 2 TBSP of Ricotta mixture, and set them into the 8×13 pan on top of the sauce. Arrange them in rows. They will be a tight fit.
7. Once all shells are stuffed and arranged, pour remaining Marinara sauce evenly over the tops of the shells.
8. Sprinkle evenly with remaining mozzarella cheese.
9. Cover with foil and bake at 350 for 20 min. Uncover and continue baking an additional 5-10 min.
10. Allow shells to sit/cool for about 5-10 min before serving. They will be hot.
Source:
mommysonadiet.net