Brown the ground beef in a skillet over medium heat until fully cooked.
In the crockpot, add the cooked ground beef along with black beans, corn, diced tomatoes, and taco seasoning.
Stir to combine all ingredients well, ensuring even distribution of spices and flavors.
Cover and cook on low for 6-8 hours or on high for 3-4 hours, until heated through.
Once cooked, stir in half of the cheddar cheese and the sour cream.
Sprinkle the remaining cheddar cheese on top and cover until melted.
Top with crushed tortilla chips just before serving for added crunch.