Add about 1 cup of water to the bottom of the instant pot along with a pinch of salt. Place the steamer basket over the water and add the chopped sweet potato. Add the lid to the instant pot and flip the vent to seal.
Set the instant pot to manual, high pressure, 14 minutes. Immediately release the pressure once cooked
Carefully remove the steamer basket, dumping the cooked sweet potato in a large bowl. Add the ghee, coconut milk, salt, pepper, and garlic powder. Use a potato masher to mash to your desired consistency, adding more milk for creamier mashed potatoes.
Season further to taste and serve with chopped chives.