01 -  Set the oven to 175°C and allow it to fully preheat. 
 02 -  Heat a large skillet over medium heat. Add the ground beef or turkey; cook, breaking it up with a spatula, until well browned. Drain excess fat as needed. 
 03 -  Add diced bell peppers, onion, corn, black beans, and taco seasoning to the skillet. Continue cooking for 5 minutes, stirring frequently, until vegetables are softened. Season with salt and pepper to taste. 
 04 -  Place one flour tortilla in the bottom of a 23x33 cm baking dish. Spread half of the meat and vegetable mixture evenly over the tortilla. Dollop with half the sour cream and sprinkle with shredded cheddar cheese. 
 05 -  Top with a second tortilla. Spoon over the remaining meat mixture, half of the crushed tortilla chips, another layer of sour cream, and additional cheese. 
 06 -  Cover with the last tortilla, scatter the remaining cheese on top, and finish with the rest of the crushed tortilla chips. 
 07 -  Cover the dish with aluminum foil and bake for 20 minutes. Remove the foil and bake an additional 10 minutes, or until cheese becomes bubbly and golden. 
 08 -  Allow the casserole to cool for several minutes before slicing and serving.