Preheat your oven to 375°F and lightly grease a small baking dish.
Place the chicken breast in a pot of simmering water and cook for 12-15 minutes until fully cooked, then remove and shred with two forks.
In a small skillet, heat the avocado oil over medium heat and sauté the diced bell peppers and red onions until they are soft and translucent.
In a small mixing bowl, whisk together the tomato puree, chili powder, cumin, garlic powder, onion powder, sea salt, and black pepper to create the red chili sauce.
Combine the shredded chicken with the sautéed vegetables and 2 tablespoons of the prepared chili sauce.
Warm the corn tortillas in a dry pan for 30 seconds per side to make them pliable, then fill each tortilla with the chicken mixture and roll tightly.
Place the rolled tortillas seam-side down in the baking dish and pour the remaining chili sauce evenly over the top.
Sprinkle the shredded cheddar cheese over the enchiladas and bake for 15 minutes until the cheese is melted and bubbling.
Serve hot topped with a dollop of Greek yogurt and freshly chopped cilantro.