In a large skillet over medium heat, add the ground beef (or turkey). Cook until the meat is browned and fully cooked, about 6-8 minutes. Use a slotted spoon to drain any excess fat from the skillet.
Transfer the cooked meat to your crockpot. Add the drained black beans, rinsed kidney beans, drained corn, diced tomatoes with green chilies, and the taco seasoning. Stir the mixture well until all ingredients are evenly combined.
Pour the salsa over the bean and meat mixture in the crockpot. Gently stir again to ensure the salsa is well dispersed throughout the ingredients.
Cover the crockpot and select the cooking time. Cook on low for 4-6 hours or on high for 2-3 hours until all layers are heated through and flavors meld beautifully.
Approximately 30 minutes before serving, stir in the crushed tortilla chips along with half of the shredded cheese, mixing well until incorporated.
Top the casserole with the remaining shredded cheese. Cover the crockpot and allow the cheese to melt, about 15-20 minutes, before serving.