Boil chicken breasts in water with bouillon cube for 10-15 minutes until cooked through and internal temperature reaches 165°F.

Remove chicken and shred using a hand mixer on low speed or two forks. Set aside.

In a large skillet, melt butter and olive oil over medium heat. Add chopped onion, taco seasoning, green chilies, diced jalapeños, and jalapeño brine.

Sauté for 2-3 minutes until onions are golden and fragrant.

Reduce heat to medium-low and add softened cream cheese. Stir continuously for 2-3 minutes until fully melted and smooth.

In a large bowl, combine shredded chicken, Colby jack cheese, and the cream cheese sauce mixture. Mix until chicken is evenly coated.

Preheat oven to 375°F (190°C). Spray a 9x13-inch baking dish with cooking spray.

Spoon 1/2 to 3/4 cup of chicken mixture down the center of each tortilla. Roll tightly and place seam-side down in the prepared dish.

Pour enchilada sauce over the rolled tortillas, covering them completely.

Sprinkle freshly shredded cheddar cheese evenly over the top.

Cover dish with aluminum foil and bake for 20 minutes.

Remove foil and bake uncovered for an additional 20 minutes until cheese is golden and bubbly.

Let rest for 5 minutes before serving. Garnish with cilantro, sour cream, or diced tomatoes if desired.