Preheat the oven to 400F degrees and spray a 9"x 13" baking dish with nonstick cooking spray and set aside.
In a large skillet over medium high heat, melt the butter. Add in the onions and cook for 3-4 minutes, or until the onions are softened and translucent.
Next, stir in the flour and keep stirring while it cooks for 1-2 minutes
Pour the chicken stock into the flour mixture along with all of the seasonings and stir well.
Bring to a boil, then turn down the heat and allow the mixture to simmer. Stirring frequently for another 1-2 minutes until the mixture has thickened and is well combined.
Remove from the heat and mix in the cream cheese cubes and milk until well blended.
Toss in the vegetables and shredded chicken and stir to coat.
Spread the mixture into the bottom of the prepared baking dish.
Place tater tots in a single layer on top of the chicken mixture. Bake in the preheated oven for 35 minutes, or until the tater tots are cooked through and a golden brown color.
Finally, sprinkle the shredded cheese evenly over the top of the tater tots.
Bake for another 4-5 minutes for the cheese to melt (or place under the broiler for 1-2 minutes for a crispier cheese topping.)
Garnish with chopped parsley (optional)and serve immediately.
Notes
Tater tots do not need to be defrosted for this.
Use your favorite cheese, we like cheddar.
You can use any shredded cooked chicken you'd like.