Preheat oven to 350°F.
Bring a large pot of water to a boil.
Add the pasta, as well as a generous amount of salt, and stir.
Cook the pasta until al dente, about 15 minutes.
Drain the pasta and toss with olive oil. Set aside.
Pour the marinara sauce into a 8”x 8” baking dish and move around to form an even coat.
In a mixing bowl, combine the filling ingredients and stir together well. Season together with salt and pepper.
Using a spoon, scoop a small amount of the filling and stuff into a pasta shell.
Nestle the stuffed shell into the baking sheet and repeat with the remaining shells until the baking dish is filled.
Top the baking dish with a sprinkle of parmesan.
Tightly cover the baking dish with aluminum foil and bake for 20 minutes.
Remove the foil and continue to bake for an additional 5 minutes or until the parmesan begins to bubble and lightly brown.
Remove from the oven and allow to rest for 5 minutes before serving.