Possible Clues:

• Basic ingredients giving finishing touch
• In charge of gin production? Topping!
• Topping to see potential killer beheaded - good!
• Sugar preparation used for decorating cakes
• Frosting over
• As on the cake, it's the nicest part
• Freezing some confectionery
• Piping on a coat
• - - on the cake
• Sweet thing gambling on going topless