Sausage, Spinach and Cheese Stuffed Shells

1 (12oz) pkg jumbo pasta shells (about 36)
2 tbsp olive oil
1/2 cup finely chopped onion
3/4 lb bulk sweet Italian sausage
2 cloves garlic, minced
1 large egg
1 (15oz) container ricotta cheese
1 (9oz) box frozen chopped spinach, thawed, squeezed dry
3/4 cup grated Parmesan cheese
4 oz shredded mozzarella
1/2 tsp salt
1/2 tsp pepper
1 (32oz) jar tomato sauce

1. Bring a large pot of salted water to a boil; add pasta shells and cook according to package directions. Drain in a colander, rinse under cold water to stop the cooking.

2. Heat oil in large skillet on medium-high heat; add onion and cook until softened. about 5 minutes. Add sausage, breaking up into smaller bits with a wooden spoon. Cook, stirring frequently, until sausage is no longer pink, about 5 minutes. Add garlic and cook 1 minute longer. Remove pan from heat.

3. Beat egg lightly in a large bowl; stir in ricotta, spinach, 1/2 cup of Parmesan, mozzarella, salt, pepper and the cooled sausage mixture until blended. Fill pasta shells with mixture.

4. heat oven to 350. Spread 1 cup of the tomato sauce over the bottom of a 3qt baking dish. Arrange stuffed shells in dish. Spread remaining tomato sauce over pasta shells. Cover dish with foil; bake for 30 minutes, until hot and bubbling. Remove foil; sprinkle with remaining Parmesan cheese. Bake uncovered for 10 minutes longer.

Serves 8.