Preheat the oven to 350°F (175°C).
Peel and chop the Yukon Gold potatoes into uniform chunks.
Boil the potatoes in salted water until tender, about 15-20 minutes.
Drain the potatoes and return them to the pot.
Mash the potatoes until smooth with no lumps.
Add heavy cream, butter, sour cream, garlic powder, and salt, mixing until combined.
Transfer the mixture to a greased baking dish, smoothing the top.
Bake in preheated oven for about 30 minutes, or until golden and bubbly.
Garnish with fresh chives before serving.
