Best mashed potatoes I had recently was at a friends house. She boiled the potatoes in just enough water to cover them - and added 4 whole garlic cloves (peeled). She mashed the garlic in with the potatoes when done cooking - adding butter, some sour cream and just enough cooking water to make them creamy. Dang good! Almost better than the fish fry they made also.
I'll have to try then!