In a large saucepan over high heat, add sweet potatoes; bring to a boil. Reduce heat and simmer uncovered for 15 minutes, or until potatoes are tender when pierced with a fork.
Drain potatoes in a colander and return to pot, away from heat. Add butter, garlic, dried herb of choice, brown sugar, and heavy cream.
With a hand mixer or potato masher, beat mixture until smooth and creamy. Season with salt and freshly ground black pepper, to taste.