Preheat your oven to 375°F (190°C).
In a small saucepan over medium heat, combine the olive oil, ancho chili powder, cumin, oregano, garlic powder, and onion powder; toast for 1 minute until highly fragrant.
Whisk in the tomato puree and chicken broth, simmering for 5-7 minutes until the sauce thickens slightly.
Season the sauce with sea salt and black pepper, then remove from heat.
Poach or bake the chicken breast until cooked through, then shred with two forks and toss with 2 tablespoons of the prepared sauce.
Warm the corn tortillas in a dry skillet for 30 seconds per side to make them pliable and prevent cracking.
Place a portion of shredded chicken in the center of each tortilla, roll tightly, and place seam-side down in a small baking dish.
Pour the remaining ancho sauce evenly over the tortillas and top with shredded Monterey Jack cheese.
Bake for 10-12 minutes until the cheese is bubbly and the edges of the tortillas are slightly crisp.
Garnish with fresh chopped cilantro before serving.