I've been to two count 'em Two weddings where at the cocktail hour they had a potato bar...
they had a "bar tender" who would serve you a scoop or two of the mashed of your choice...I think they had Yukon Gold, Idaho and sweet potato... and then you dressed it yourself they had brown gravy, brown sugar, crushed nuts, green onions, various shredded cheeses, bacon, of course bacon, sour cream, butter