Preheat your oven to 375°F (190°C).

In a large skillet, heat the olive oil over medium heat. Add the diced onion and sauté until translucent, about 3–4 minutes.

Add the ground beef to the skillet, breaking it apart with a spatula. Cook until browned and fully cooked, about 5–7 minutes. Drain any excess fat.

Stir in the black beans, diced tomatoes with green chilies, frozen corn, taco seasoning, salt, and pepper. Mix well and simmer for 5 minutes to allow the flavors to meld.

Spread the beef mixture evenly in the bottom of a greased 9x13 inch baking dish.

In a separate bowl, mix the sour cream and half of the shredded cheddar cheese. Spread this mixture over the beef layer in the baking dish.

Unroll the crescent roll dough and lay it over the sour cream mixture, pressing the edges to seal. Sprinkle the remaining cheddar cheese on top.

Bake in the preheated oven for 25–30 minutes, or until the crescent rolls are golden brown and fully cooked.

Remove from the oven and let it cool for a few minutes before serving.