Do not overcook the pasta shells; cook just until al dente to prevent tearing. Drain spinach thoroughly to avoid a watery filling. You can assemble the dish up to 24 hours in advance and refrigerate before baking. For freezing, assemble before baking and freeze up to 3 months, thawing overnight before cooking. Garnish with fresh basil before serving if desired.
Keyword cheesy baked pasta, ricotta stuffed pasta shells, spinach ricotta stuffed shells, vegetarian pasta bake