Garlic Mashed Potatoes

For a date night Jason made these yummy potatoes to accompany strip steak and garden salad.  They were so good, I couldn't leave them alone.  The original recipe said this yields 4 servings, but I believe that 6 would be more accurate.
 
1 1/2 pounds red potatoes (about 8 small), quartered, skin left on
1 1/2 teaspoons kosher salt, divided
1/4 teaspoon fresh ground black pepper
1 teaspoon garlic powder
1/2 cup sour cream
1/2 cup grated Parmesan cheese
1/4 cup unsalted butter, cut into pieces

1. Place potatoes in a large pot or dutch oven. Add enough water to cover the potatoes. Stir in 1 teaspoon of the kosher salt. Bring to a boil, then reduce heat, cover and simmer about 20 to 25 minutes.
2. Meanwhile, place the remaining 1/2 teaspoon kosher salt, pepper, garlic powder, sour cream, Parmesan cheese and butter in the bowl of an electric mixer.
3. When potatoes pierce easily with a paring knife, remove from heat and drain. Add potatoes to the bowl with the other ingredients and mix on medium speed until mostly smooth (there may be some lumps, but we usually don't mind that). Serve.