Place sweet potatoes in a large saucepan or Dutch oven and cover with water.
Bring the water to a boil over medium-high heat, then lower to medium and allow to simmer for about 10-12 minutes. Cook just until the sweet potatoes are fork tender.
Drain the water and either return the sweet potatoes to the pot or place the sweet potatoes into a large bowl. Mash sweet potatoes.
Add garlic, sour cream, unsalted butter, broth, and continue to mash until smooth.
Add half of the green onions and half of the chopped parsley. Stir together.
Season with salt and pepper and stir to combine.
Garnish with remaining green onions and parsley.
Notes
Makes approximately 6-8 side dish servingsStorage: store in an airtight container in the refrigerator for up to 4 or 5 days. Freeze: store in a freezer safe container in the freezer for up to two months. Allow to thaw completely over night in the refrigerator before reheating and serving.