Cook the jumbo shells according to package directions.Once cooked (not all the way through, they’ll cook more in the oven), drain and set aside to cool a little. Rinse the shells with cold water after cooking to help the cooling process go faster.Preheat the oven to 350 degrees F.
Make the filling
Add the ricotta cheese, 1 1/2 cups of the mozzarella cheese, 1/2 cup of the parmesan, parsley and garlic to a large bowl, and mix well. Add the egg, and salt and pepper to taste (I suggest a good pinch of each) then mix until well blended.
Stuff the shells
Add a little marinara sauce to the bottom of your baking dish, just enough to coat the surface.Stuff the cooked shells with the cheese mixture, and line them up in the baking dish.Pour remaining marinara sauce over the top, and sprinkle with remaining cheeses.
Bake for 30 minutes.Allow to cool for 5 minutes, and serve.
When cooking the shells, don't cook them until they are super soft. They'll cook more in the oven, and you want them to be intact for stuffing, not floppy and easy to tear.What to do with leftoversStore in a covered container in the refrigerator for up to 4 days. Reheat until it is piping hot!Substitutions/AdditionsYou could add a little Italian seasoning to the cheese filling, I suggest 1 teaspoon to start with.You may use cottage cheese in place of the ricotta if you that is what you have on hand. I like to blend it a little with a fork to make the curds smaller.Freezing instructionsThis recipe can be frozen before baking. Cover tightly with foil and wrap with plastic wrap. Freeze. On cooking day just remove from the freezer and bake, adding 20 minutes onto the cooking time if baking from frozen.