Preheat the oven to 400 degrees. Use a pizza cutter to slice the tortillas into thin strips. Line a baking sheet with foil and coat it with non-stick spray. Spread the tortilla strips out in a single layer and spritz lightly with more non-stick spray. Sprinkle lightly with salt.
Bake the tortilla strips for 15-20 minutes or until they are golden brown and crispy. Stir the tortilla strips half way through cooking.
While the tortilla strips are baking, cut the head of lettuce into small pieces. Rinse the lettuce and drain well (or use a salad spinner). Also chop the tomato and slice the green onions. Rinse the black beans in a colander to remove the starchy canning liquid. Remove the corn from the freezer and allow it to thaw.
Whisk together all of the ingredients for the dressing (yogurt, buttermilk, mayonnaise, salt, garlic powder, chili powder, cumine, and cayenne). Makes about 1.5 cups or 6 servings of 1/4 cup each.
Once the tortilla strips are finished cooking, the dressing is made, and all of the salad ingredients are prepped, build the salad! You can either build one big salad and then serve or build individual portions. Layer the lettuce first, then black beans, corn, tomato, shredded cheese, green onion, and a few tortilla strips on top.