Heat the olive oil in a large skillet over medium-high heat. Add the cubed chicken.
Sprinkle the chili powder, salt, pepper, and oregano over the chicken and stir until evenly coated. Cook for 5 to 7 minutes, stirring occasionally, until browned and cooked through, then transfer the chicken to a plate.
In the same skillet, add the diced onion, garlic, and bell peppers. Cook for 3 to 4 minutes, until the vegetables start to soften.
Stir in the black beans, corn, and diced tomatoes. Simmer for 5 minutes, stirring occasionally, until everything is hot and the flavors blend.
Add the chicken back to the skillet and stir to combine.
Stir in the lime juice, then sprinkle the Mexican blend cheese over the top. Cover for 2 to 3 minutes, just until the cheese melts, then serve.