An easy and foolproof way to make stuffed shells: use the crockpot! The pesto gives these stuffed shells delicious flavor and the three cheeses used also don't hurt to use either :)
Make Crockpot Bolognese Sauce according to directions.
Spread about 1 1/2 cups of sauce into the bottom of your crockpot to serve as a base and a no-crunchy-or-burned-noodle-barrier. Set aside.
For the filling, stir all ingredients together until combined. Spoon filling into cooked shells, stuffing evenly. Place into bottom of crockpot, onto that sauce.
Spoon more sauce over the top of each shell and sprinkle with extra cheese if you feel so inclined.
Cover and cook 1 1/2 hours on high or 3 hours on low OR until hot all the way through. Sprinkle with parsley flakes and serve.**Non-crockpot directions: Place shells into 9x13 baking dish, cover with foil and bake at 350 for 30 minutes or until hot.