Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a large skillet over medium heat, combine the cooked ground beef, taco seasoning, black beans, corn, and diced tomatoes. Stir well and cook for about 3-5 minutes until heated through. Remove from heat and stir in the chopped cilantro.
Roll out the refrigerated pizza dough on a lightly floured surface into a large rectangle about 1/4 inch thick.
Cut the dough into strips approximately 2 inches wide.
Spoon a generous amount of the taco mixture down the center of each strip, leaving enough space on the edges for sealing.
Sprinkle a tablespoon of shredded cheddar cheese on top of the taco mixture.
Fold the sides of the dough over the filling to enclose it, pinching the edges to seal tightly.
Place the sealed taco sticks on the prepared baking sheet, and brush the tops with the beaten egg.
Bake in the preheated oven for about 15-20 minutes or until golden brown.
Let the cheesy taco sticks cool for a couple of minutes before serving.