To a large skillet, add the olive oil, chicken, and cook over medium-high heat for about 5 minutes, or until chicken is cooked through; stir and flip intermittently to ensure even cooking.
Evenly sprinkle with the taco seasoning, add the red bell pepper, black beans, corn, tomato sauce, and simmer for about 2 to 3 minutes, or until warmed through.
Reduce the heat to medium-low, add the shredded Mexican cheese blend, and cover the skillet with a lid to help the cheese to melt for about 1 minute, or until melted. Stir to combine.
Garnish with green onions, cilantro, and optionally serve with Spanish rice or over your favorite tortilla chips.