Instructions

1. Heat your oven to 400° F.  Prepare an oven safe baking dish (something around 8 x 11 inches) with non-stick cooking spray.
2. Heat 1 tablespoon of oil in a medium skillet over medium-high heat and add the onion and corn.  Cook, stirring, until the onion begins to soften (3 to 5 minutes).
3. Transfer the vegetables to a large bowl and add the chicken, Monterey Jack, 1 teaspoon salt, and ¼ teaspoon pepper.  Mix together to combine.
4. Line the bottom of the baking dish with tortillas, covering the entire bottom and overlapping if need be.  (My dish took 6 tortillas across the bottom.)
5. Evenly spread the chicken mixture across the tortillas and cover with a second layer of tortillas.  If desired, sprinkle more shredded cheese on top.
6. Bake until heated through, about 8 to 10 minutes.
7. Meanwhile, in a food processor, pulse the tomatillos, jalapeño, cilantro, lime juice, and ½ teaspoon salt until finely chopped and blended.
8. Serve the tostadas with the salsa and some sour cream.