Preheat oven to 375 degrees.

In a large mixing bowl add ricotta, 1 cup of Parmesan cheese, 1 egg, and drained spinach and stir until blended.

Spoon approximately about 1 tbsp mixture into each pasta shell.

Spread half the jar of pasta sauce on the bottom of a large baking dish.

Place the shells in the prepared dish until it is full.

Pour the remaining 1/2 jar of pasta sauce on top of the shells, spreading to cover.

Sprinkle on 1 cup of mozzarella cheese and remaining 1/2 cup Parmesan cheese.

Cover with aluminum foil and bake for 35-40 minutes.

Serve hot and enjoy!