Preheat your oven to 375°F.
In a small skillet, sauté the diced yellow onion and red bell pepper in olive oil over medium heat until softened and slightly caramelized.
In a small saucepan, whisk together the tomato puree, water, chili powder, ground cumin, garlic powder, sea salt, and black pepper; simmer for 5 minutes to meld the flavors.
In a medium bowl, combine the cooked shredded chicken breast with the sautéed vegetables and 2 tablespoons of the prepared red chili sauce.
Warm the corn tortillas slightly to prevent cracking, then dip each one into the sauce to lightly coat both sides.
Fill each tortilla with the chicken and vegetable mixture, roll tightly, and place seam-side down in a small baking dish.
Pour the remaining red chili sauce over the top of the enchiladas and sprinkle evenly with the shredded cheddar cheese.
Bake for 15 minutes until the cheese is bubbly and the edges of the tortillas are slightly crisp.
Garnish with freshly chopped cilantro before serving hot.