Preheat the oven to 375°F.
In a large skillet, heat olive oil over medium heat. Add the chopped onion and sauté for about 3-4 minutes until translucent. Stir in the minced garlic and cook for an additional 1 minute.
Add the ground chicken to the skillet, breaking it apart with a spatula. Cook until browned and fully cooked, about 5-7 minutes.
Stir in the chili powder, cumin, paprika, salt, and black pepper. Mix well, then add the black beans and corn. Cook for another 2-3 minutes until everything is heated through.
Arrange the corn tortillas in a muffin tin, pressing them down to form little cups. Spoon the chicken mixture into each tortilla cup, filling them generously. Top each with shredded cheddar cheese.
Bake in the preheated oven for 15-20 minutes, or until the cheese is melted and the tortillas are slightly crispy.
Remove from the oven and let cool for a few minutes. Drizzle with salsa and sprinkle with fresh cilantro if desired. Serve with sour cream or Greek yogurt on the side.