Preheat your oven to 375°F (190°C).
Dice the bell pepper and red onion into small, uniform pieces.
In a medium mixing bowl, combine the shredded cooked chicken breast, Greek yogurt, cumin, chili powder, sea salt, and black pepper until well incorporated.
Slice the corn tortilla into thin, bite-sized strips.
Spread half of the red enchilada sauce across the bottom of a small oven-safe baking dish.
Layer the chicken mixture, diced peppers, onions, and tortilla strips into the dish.
Pour the remaining enchilada sauce over the top and sprinkle evenly with the shredded cheddar cheese.
Bake for 20 minutes, or until the sauce is bubbling and the cheese has melted into a golden crust.
Remove from the oven and garnish with freshly chopped cilantro before serving warm.