So cool that ... wouldn't melt in their mouth (6)
I believe the answer is:
butter
(Other definitions for butter that I've seen before include "Spread for bread" , "Type of toffee" , "Dairy spread" , "Spread derived from cream" , "Milk product" .)
I believe the answer is:
butter
(Other definitions for butter that I've seen before include "Spread for bread" , "Type of toffee" , "Dairy spread" , "Spread derived from cream" , "Milk product" .)