In medium saucepan on medium-high heat, combine salt, potatoes and enough water to cover the potatoes. Cover and bring to a boil. Reduce heat to medium and simmer 8-10 minutes, or until desired tenderness. Drain the potatoes.
Add the butter, milk, sour cream and garlic powder to the potatoes. Use a potato masher to mash the potatoes until creamy. Add more milk if they seem dry. Taste and add more garlic powder, if desired. Season with salt and pepper, to taste. Serve hot.