Make sure you use good quality jumbo shells and be delicate with them! Followed the recipe fairly closely, except for sprucing up the ricotta mixture with garlic & onion powders and basil. I toasted my walnuts beforehand, as I believe it makes an honest difference to your dish. As mozzarella is a mild-flavored cheese, I chose to use a five-cheese Italian blend and it was a nice touch. I appreciated the "meaty" texture of the walnuts, though I would reduce them to a 1/2 c next time. Pine nuts would be an excellent substitution too. Preferring a thicker filling, I'll use only 1 egg next time. With plenty of wiggle room in this recipe, I can't wait to incorporate some variations (spinach in the filling, maybe using manicotti vs. shells or even making a lasagna?), as this tasty baked pasta will remain on our Meatless Monday rotation.