Possible Clues:

• Tops a tart, say
• Cools, as drinks
• Completes the cake
• Desserts that may cause brain freeze
• Cold comfort provides services in the end
• Confectionery from van is offered outside church?
• That is what won't make things hot any day
• Cinches, as a win
• Ensures, slangily
• Finishes making, as a black-and-white cookie