Get 8-10 assorted herbs and spices and small bowls to put them in. Make sure to use some easy spices everyone knows (cinnamon, basil), as well as some harder to guess spices. Number the small bowls so the guests know which one they are guessing. Then just line the bowls up on a table or tray and have each player smell and look at each spice to guess what it is. Give your guests paper and pens to write their answers on and have write down what they think it is. The player with the most correct wins.
To give the game more challenge you can have them guess by smell alone, just wrap aluminum foil over the tops of the bowls and poking some small holes in it so just the smell comes through. Without the visuals sometimes this game can stump the greatest of home cooks.
For a little fun with the bride, during her turn have the guests start making suggestions that lead the bride completely astray! Most brides really goof things up though they may know the contents perfectly well!