ALFRED PUT THE SOUP IN A MICROWAVEBLE CROCK BECAUSE HE KNEW BRUCE WASNT GOING TO EAT IT WHILE IT WAS HOT OMGGGGGG
I imagine there were too many nights where Alfred came down to the cave only to find his rich beef stew, Italian minestrone soup or clam chowder gone cold.
Personally, I headcanon that the next time, he just made chilled Russian borscht, fully knowing that Bruce absolutely detests beets.
Alfred came down later to find Bruce sitting in his cape and cowl, eyes narrowed at the bright pink soup… but he knew exactly what he had done to deserve this. So he ate it, spoon by spoon, mouth set in a firm, determined line in between mouthfuls… and requested that his soup be put in a canister for him to take on patrol next time.