Preheat your oven to 375°F (190°C).
Heat olive oil in a skillet over medium heat and sauté diced chicken, bell peppers, and onions until the chicken is cooked through and vegetables are tender.
In a small mixing bowl, whisk together the tomato puree, chili powder, cumin, garlic powder, sea salt, and black pepper to create the enchilada sauce.
In a separate bowl, combine the Greek yogurt with 2 tablespoons of the prepared chili sauce and the sautéed chicken and vegetable mixture.
Warm the corn tortillas slightly to make them pliable, then fill each with the creamy chicken mixture and roll tightly.
Place the tortillas seam-side down in a small baking dish, pour the remaining chili sauce over the top, and sprinkle with shredded cheddar cheese.
Bake for 15 minutes until the cheese is melted and bubbling, then serve warm.