Adjust the oven rack to the middle position and preheat the oven to 350 degrees F. Use 1 1/2 tablespoons of the oil to lightly brush both sides of the tortillas; sprinkle them with salt. Arrange directly on the oven rack and bake, turning once, until crisp and golden brown, about 5 minutes on the first side and 3 minutes on the second side (use the tip of a knife to deflate any air pockets that may balloon during baking); set aside.
Mix the remaining 1 tablespoon oil with the garlic powder, cumin, and oregano and rub onto the corn to evenly coat. Sprinkle generously with salt.
Meanwhile preheat a gas grill with all burners on high for about 10 minutes. Use a wire brush to clean the grill rack, then use tongs to wipe a vegetable oil-soaked rag over it. Close the lid and return to temperature. When very hot, place the corn on the hot rack; cover and grill, turning as needed, until spotted with brown, about 10 minutes.
Combine the lettuce, tomatoes, bell pepper, scallions, black beans, and cheese in a large bowl. To make the dressing, stir together the sour cream and salsa. Add half the dressing to the salad and toss to coat. Heap a portion of salad onto each flour tortilla. Serve with ears of corn alongside. Garnish if you like with a little extra sour cream and serve with additional dressing alongside.
Reprinted from Cook Without a Book: Meatless Meals (c) 2011 by Pam Anderson. Permission granted by Rodale, Inc. Available wherever books are sold.
Photograph by Quentin Bacon.