If using a steamer basket, add water to the Instant Pot and place sweet potatoes in the steamer basket. Place steamer basket in the Instant Pot. Otherwise, add sweet potatoes and 1 cup water directly into the Instant Pot. Lock the lid in place and set the pressure valve to "sealing".
Select "high pressure" and set the timer to 3 minutes. When the 3-minute timer is up, do a quick pressure release to remove all steam at once. Careful, a lot of hot steam will come out!
Drain water from the Instant Pot. Add butter to the warm pot. It should melt over "keep warm" but "sauté" can be selected if needed. Once melted, add the cooked sweet potato and milk. Mash with a potato masher until smooth.
Add the light brown sugar, cinnamon, nutmeg, vanilla extract and pinch of salt. Stir to combine. Enjoy hot, garnished with pecans and an extra sprinkle of brown sugar and cinnamon.
If the potatoes aren't fork-tender and easily mashable after pressure cooking you can cook on high pressure for 1 more minute. Do a quick pressure release, repeating as needed.
Cooking equipment: I recommend using a steamer basket for this recipe to make clean-up easier. If you don't have a steamer basket, you can place the sweet potatoes directly into the Instant Pot.
For ultra-creamy sweet potatoes, you can puree the hot sweet potatoes with an immersion blender. This will remove any stringy sweet potato bits.
To toast pecans, set your Instant Pot to "sauté". Once it reads "hot", add ¼ cup pecans. Toast for 1-2 minutes, stirring frequently to prevent burning.
To make dairy-free: Swap out butter for vegan butter or coconut oil and use your favorite unsweetened, unflavored non-dairy milk.
Leftovers and reheating: Keep leftovers refrigerated for 3-4 days in a closed container. Reheat individual servings in the microwave or on the stove over medium-low heat with an extra splash of milk.
Freezing: Let the mashed potatoes cool to room temperature before transferring to a freezer-safe container. Freeze for up to 3 months. When ready to use, let thaw overnight in the fridge.