Prepare the vegan pesto first. Combine basil leaves, pine nuts, and garlic in the food processor and pulse until well incorporated. Add nutritional yeast, sea salt, and lemon juice and pulse until combined. Slowly add in olive oil a little at a time while the food processor is running to thin out the pesto. Once thoroughly combined, set pesto aside for later. You can place it in the refrigerator to thicken it a little more for easy spreading.

Put all ingredients for vegan mozzarella in a high speed blender and blend until completely smooth, about 1 minute. Pour mixture onto a skillet over medium high heat and stir with a wooden spoon. After a few minutes, mixture will look like it's curdling or separating, but just keep mixing. Soon the mixture will thicken into a stretchy, mozzarella-like consistency, after 3-5 minutes total. Set aside.

Slice roma tomatoes. Divide bread into 4 sandwiches. Place a few basil leaves on each bottom slice. Top with a few dollops of "mozzarella." You may need to stretch and cut the mozzarella into pieces for each sandwich. Top with tomato slices. Top with a few dollops of pesto. Repeat layers until you are satisfied with the sandwiches. Serve immediately. Enjoy!