Preheat your oven to 190°C (375°F). Grease a 23 x 33 cm casserole dish.
In a large bowl, combine the shredded, cooked chicken, concentrated cream of chicken soup, sour cream, milk, dry ranch seasoning, and 1 cup shredded Colby-Jack cheese. Mix well.
Transfer the chicken mixture to the prepared casserole dish and spread evenly.
Sprinkle half of the cooked, crumbled bacon over the chicken mixture.
Arrange the frozen hash browns in a single, even layer over the chicken and bacon.
Bake in the preheated oven for 30 minutes.
Remove the casserole dish from the oven and sprinkle the remaining 1/2 cup of shredded Colby-Jack cheese over the hash browns.
Return the casserole dish to the oven and bake for another 10 minutes, until the cheese is melted and bubbly and the hash browns are golden brown.
Remove the casserole from the oven and garnish with the remaining cooked bacon and sliced spring onions. Let cool slightly before serving.
