15 ounces ricotta cheese
2 large eggs
1 (10 ounce) package frozen chopped spinach, thawed and squeezed of liquid
1 cup shredded mozzarella cheese
½ cup grated Parmesan cheese, divided
1 ½ tablespoons white sugar
⅛ teaspoon salt
¼ teaspoon ground black pepper
1 teaspoon oregano
12 manicotti shells
1 (45 ounce) jar spaghetti sauce
Mix ricotta cheese and eggs together in a medium bowl until blended. Stir in spinach, mozzarella cheese, 1/4 cup Parmesan cheese, sugar, salt, and pepper. Place in fridge for about 15 minutes to firm up. Spoon cheese mixture into a plastic baggie. Make a small cut at a bottom corner of the baggie and squeeze (pipe) cheese mixture into the uncooked pasta shells. Pour 1/2 cup spaghetti sauce into a medium baking dish; spread to cover the bottom. Arrange stuffed shells in a single layer over sauce. Pour remaining sauce over shells. Cover and chill in the refrigerator, 8 hours to overnight. When ready to bake, preheat the oven to 400 degrees. Remove shells from the refrigerator. Bake, covered, in the preheated oven for 40 minutes. Uncover, sprinkle with remaining Parmesan cheese, and bake for 15 more minutes.
