Preheat the oven to 375°F (190°C).
In a bowl, whisk together the sour cream and the green enchilada sauce until smooth and evenly combined.
In a separate bowl, combine the shredded BBQ chicken, corn, and drained black beans until evenly mixed.
Spoon a heaping 1/4 cup of the chicken mixture into the center of each tortilla, roll tightly, and place seam-side down in a 9x13-inch baking dish.
Pour the sour cream and enchilada sauce mixture evenly over the rolled enchiladas, then sprinkle the shredded cheddar cheese on top.
Bake for 20–25 minutes, until heated through and the edges are bubbly.
Garnish with pico de gallo and serve hot.