They could have dropped balls of dough in soup or stew for dumplings. Jane Auel in her Clan of the Cave Bear series of books describes making soup/stew by lining a hole in the ground with skins and dropping in heated stones. Easy enough to drop in balls of dough too. After the period of relatively high development in Europe, there were a series of severe drops in temperature, 3 at least from 28000 to 22000 BC. I believe the one at 22,000 was caused by the giant eruption of sakara-jima in Japan that left a caldera that is now 15 miles in diameter.
Neandertals invented soup?
http://www.freerepublic.com/focus/news/1607603/posts?page=17#17
N eating habits:
http://www.freerepublic.com/focus/news/1966704/posts