01 - 
                In a large pot, bring water to a boil with a tablespoon of salt if desired. Cook jumbo pasta shells until al dente, then drain and set aside.
              
              
              
                02 - 
                Preheat oven to 375°F (190°C).
              
              
              
                03 - 
                Defrost frozen spinach by placing it in the refrigerator, on the counter, or microwaving at 30% power in 2-3 minute intervals. Strain using a fine mesh strainer and press out excess water until lightly damp.
              
              
              
                04 - 
                If not already prepared, make vegan ricotta in a food processor. Add spinach to the ricotta and pulse until combined. Taste and season with salt or lemon if needed.
              
              
              
                05 - 
                Spread a thin layer of marinara sauce at the bottom of a 9x13 baking dish, ensuring even coverage.
              
              
              
                06 - 
                Fill each cooked pasta shell with the ricotta spinach mixture using a spoon or piping bag. Place filled shells into the baking dish in a single layer. Discard broken shells.
              
              
              
                07 - 
                Dollop remaining marinara sauce to cover exposed shells. Grate vegan parmesan over the shells and optionally spray with oil to assist melting.
              
              
              
                08 - 
                Bake in the preheated oven for 15-20 minutes. Check after 10-15 minutes and adjust as needed.
              
              
              
                09 - 
                Let the dish cool for 3-5 minutes before serving. Pair with vegan garlic bread if desired.