Ingredients: 

1 cup  sugar
1/2 tsp  soda
1/2 cup  buttermilk
1/2 cup  butter
1 Tbsp light Karo syrup
1 tsp  vanilla

Combine everything except vanilla.  Bring to boil in heavy pan.  Boil
for 4 minutes.  Remove from heat, stir in vanilla.  Pour while hot over
the cake (while both are hot).