Start by preheating your oven to 375°F (190°C).
In a large mixing bowl, combine the milk, heavy cream, eggs, kosher salt, fresh cracked pepper, onion powder, and garlic powder. Whisk until well blended and set aside.
In your baking dish, spread the grilled chicken pieces evenly across the bottom. Then, sprinkle the diced red and green bell peppers over the chicken.
Layer the sharp cheddar cheese and pepper jack cheese over the chicken and peppers.
Carefully arrange the frozen tater tots over the cheesy mixture.
Pour the creamy egg mixture evenly over the tater tots.
Place the casserole in your preheated oven and bake for 45-50 minutes, or until the tater tots are golden brown and crispy.
Once baked, remove the casserole from the oven and let it cool for a few minutes. Top with finely chopped green onions, and serve with fresh cilantro and a dollop of sour cream.
