Preheat your oven to 350°F (175°C) and grease a 12x9 casserole dish with cooking spray or butter.

Bring a large pot of salted water to a boil and cook 16 ounces of rotini pasta according to the package instructions, about 8-10 minutes. Drain thoroughly and transfer back to the pot.

In a large skillet over medium heat, cook 1 pound of chicken and 1 pound of crumbled bacon for about 8-10 minutes until the chicken is cooked through and golden and the bacon is crispy.

Mix together 2 packages of softened cream cheese, 1 cup sour cream, and 1 cup milk in a medium bowl until smooth. Stir in 1.5 cups Mexican Cheddar Jack cheese, diced jalapenos, and most of the green onions.

Spread the cooked rotini pasta at the bottom of the greased casserole dish. Then add the sautéed chicken and bacon mixture.

Spoon the cheese and jalapeno mixture over the layered pasta and chicken, gently stirring to combine without over-mixing.

Sprinkle the remaining 0.5 cup of Mexican Cheddar Jack cheese, reserved bacon, and the rest of the green onions on top.

Bake in the preheated oven for about 20 minutes, or until the cheese is bubbling and golden brown.