Add spinach, cumin, cilantro, red onion, garlic, salt and olive oil into a blender or food processor. One will have to occasionally stop and work the spinach down with a wooden spoon or safe utensil. Incorporate all ingredients until well blended.
Use non-stick cooking spray in a large oven-safe glass pie pan and start to layer the lasagna. Start by overlapping 4 corn tortillas. Next spread half on the spinach mixture, black beans, salsa and cheese.
Repeat the process from above but this time add the jalapeños if one likes spice. Mix the mozzarella cheese with the remaining taco cheese. Sprinkle evenly over the top layer. Cover loosely with aluminum foil and for 25 minutes.
Carefully remove foil from the pie and continue to bake for 15 minutes or until cheese is golden. Remove from oven, add chopped scallions and let rest for 10 minutes before serving.