How to Make It
Preheat oven to 375°F. Arrange 5 tostadas in the bottom of a large cast-iron skillet, breaking them, if needed, to cover bottom. Top with 2/3 cup of the enchilada sauce, about 1 cup of the chicken, 2/3 cup of the Monterey Jack, and 1/3 cup of the Manchego. Repeat layers twice. Bake in preheated oven until cheese is melted and bubbles form, about 25 minutes. Serve with sour cream, jalapeño slices, and cilantro.