I need a wedding cake ,a traditional cake served at wedding receptions. 
Having a wedding, eh?  Are you talking about those multi-layer cakes with the white icing on it?
Yeah,but that has to do with Cake decorating is one of the sugar arts that uses icing or frosting and other edible decorative elements to make plain cakes 
Is that true of the groom's cake, the little side cake that's usually chocolate-flavored?
groom's cake is a wedding tradition originating in Victorian England,
Hmm, I wonder how that tradition started.  Who was the first to make a groom's cake for a wedding?
Don't know precisely,  more often in the modern age in the American South.