Preheat the oven to 375 degrees. Coat a 9 x 7 1/2 inch deep baking pan with cooking spray.
Bring a large pot of generously salted water to a boil. Cook the Jumbo Pasta shells for 9 minutes. Drain and allow the shells to cool.
Spread one half of the marinara sauce in the bottom of the pan.
Place the cup of ricotta cheese, 1 cup of mozzarella, 1/2 cup parmesan, 1/4 cup provolone, Italian seasoning, Red pepper flake, lemon zest, egg, salt and pepper in a bowl. Stir to completely combine.
Fill each shell with the ricotta mixture and place in the baking dish. Spoon the remaining marinara sauce over the shells, then sprinkle with another cup of parmesan over the top.
Cover with foil and bake for 20 minutes. Uncover and bake for an additional 10 minutes or until cheese is melted and starting to brown.