Preheat your oven to 350 F.
Boil your pasta: Bring a pot of water to a boil. Add in your pasta shells and cook them for about 10 minutes- they should be al dente. Drain your pasta and set it aside.
Prep the spinach: In the same pot, heat the garlic clove with 1 tbsp of olive oil. Saute your spinach for 4-5 minutes. Season with a pinch of salt, transfer to a bowl and set aside.
Make the tofu ricotta: For the tofu ricotta, add all of the ingredients into a blender or food processor and blend until smooth. Pour the ricotta into the bowl with the spinach and mix well.
Stuff your shells: In a large baking dish- I used a 9u0022 pie dish, but a 9 x 13 dish would work- spread a layer of marinara sauce to coat the bottom. Begin stuffing your shells with the tofu mixture, and layering them over the marinara base.
Once all your shells are stuffed, pour the remaining sauce over the top. Add spoonfuls of pesto around the dish, and sprinkle with the chopped basil.
Bake the shells: Cover your dish with foil, and bake for 15 minutes covered, and 10 minutes uncovered. You can add vegan cheese if desired before baking.
If you want to prep this dish ahead of time, I would follow all the steps up until the baking part. You can refrigerate the shells for up to 3 days, and bake them right before serving.