Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.
In a large bowl, combine the shredded chicken, black beans, corn, cheese, cumin, chili powder, garlic powder, onion powder, salt, and pepper. Mix well until all ingredients are evenly incorporated.
Place a tortilla on a flat surface. Spoon about 1/2 cup of the chicken mixture onto the center of the tortilla. Fold in the sides and roll it up tightly. Repeat with the remaining tortillas and filling.
Place the rolled chimichangas seam-side down on the prepared baking sheet. Brush the tops lightly with olive oil.
Bake in the preheated oven for 20-25 minutes, or until the chimichangas are golden brown and crispy.
Serve hot with salsa and sour cream on the side. Garnish with fresh cilantro if desired.