Preheat your oven to 425°F (220°C).

In a mixing bowl, combine the shredded hash browns, half of the cheese, salt, pepper, and garlic powder.

Press the hash brown mixture into the bottom and up the sides of a 9-inch pie dish.

Bake the crust in the preheated oven for 20 minutes until the edges are golden brown.

While the crust is baking, whisk together the eggs and milk in a bowl.

Stir in the diced vegetables and cooked meat (if using) into the egg mixture.

Remove the crust from the oven and pour the egg mixture over the hash brown base.

Sprinkle the remaining cheese on top of the filling.

Bake the quiche for another 25-30 minutes until the filling is set and slightly golden.

Let the quiche cool for a few minutes before slicing.