In a large stockpot or Dutch oven set over medium-high heat, add 1 inch of water. Set steamer basket inside and bring water to a boil.
Fill steamer basket with potatoes and cover. Reduce heat to medium and cook for 20-25 minutes or until potatoes are fork tender.
Meanwhile, in a small saucepan set over medium heat, add butter. Once the butter has melted add the garlic and cook until fragrant, about 1-2 minutes. Add milk, salt, pepper, garlic powder and paprika. Continue cooking for 5 minutes, then cover and remove from the heat.
Remove stockpot or Dutch oven from the heat, drain water, then pour the potatoes directly into the pan. Return to the stovetop and cook for 1 minute to allow any excess moisture to evaporate.
Pour into the bowl of a stand mixer fitted with the whisk attachment (or a large mixing bowl with a hand held mixer) and mix on low for 1 minute. Slowly add the warm butter/milk mixture until fully incorporated. Beat on medium-high until potatoes are light and fluffy, about 1-2 minutes.
Let potatoes stand for 5 minutes before transferring to a serving dish. Garnish with freshly chopped parsley, if desired.