Preheat your oven to 375°F (190°C).
Heat the olive oil in a skillet over medium heat and sauté the diced onion and bell pepper until they are soft and slightly caramelized.
In a mixing bowl, combine the shredded cooked chicken breast with chili powder, cumin, sea salt, and black pepper.
In a separate small bowl, whisk together the Greek yogurt and the red enchilada sauce until smooth and creamy.
Stir half of the creamy enchilada sauce into the chicken and pepper mixture to coat everything evenly.
Slice the corn tortillas into 1-inch strips.
In a small oven-safe baking dish, layer half of the tortilla strips, followed by the chicken mixture, and then the remaining tortilla strips.
Pour the rest of the sauce over the top and sprinkle with the shredded cheddar cheese.
Bake for 15 to 20 minutes until the cheese is melted and the edges are bubbling.