In which occasion did Sir Winston Churchill say, "This is now the end of the beginning... not the beginning of the end?"

"Now this is not the end.
It is not even the beginning of the end.
But it is, perhaps,
the end of the beginning."

Churchill delivered these famous words in a 1942 speech at London's Mansion House, just after the British routed Rommel's forces at Alamein, driving German troops out of Egypt. The battle marked a turning point in the war, leading Churchill to write in his memoirs, "Before Alamein we never had a victory. After Alamein we never had a defeat."
http://econwarfare.org/time-for-churchills-v-for-victory/