Preheat your oven to 375°F.
In a large pot, add the cubed potatoes and cover with water. Bring to a boil and cook for about 15-20 minutes, or until the potatoes are fork-tender. Drain the potatoes and return them to the pot.
Add the milk, butter, salt, black pepper, garlic powder, and onion powder to the potatoes. Mash until smooth and creamy.
Stir in the cheddar cheese and bacon, if using, until well combined.
Roll out the pie crust and fit it into a 9-inch pie dish.
Pour the potato mixture into the crust, smoothing the top with a spatula.
Bake in the preheated oven for 30-35 minutes, or until the crust is golden brown and the filling is heated through.
Let the pie cool for about 10 minutes before slicing. Garnish with chopped chives before serving.