An excerpt from The Churchill Centre and Museum:
Churchill, researching his life of Marlborough, had traveled to Europe on 27 August 1932 for a tour of Marlborough's battlefields, following his great ancestor's march to the Danube and visiting Munich in mid-September. Here Churchill was joined by his wife, son Randolph, daughter Sarah and Professor Lindemann. Randolph Churchill contacted a colleague, Ernst "Putzi" Hanfstaengl (a Harvard graduate acting as Hitler's press secretary) who suggested a meeting. Hanfstaengl wrote about this in his memoirs, Hitler, The Missing Years (London: Eyre & Spottiswoode 1957), quoted at length in His Father's Son.
Hanfstaengl attempted to persuade Hitler to join Churchill's dinner party at Munich's Hotel Continental, but Hitler was reluctant: "Don't they realize how busy I am? What on earth would I talk to [Churchill] about?" Hanfstaengl himself joined the party, suggesting that "Hitler might join us for coffee." It was at this point that Churchill made the famous remark: "Tell your boss from me that anti-Semitism may be a good starter, but it is a bad sticker."
Hanfstaengl sniffed at that comment, but was tantalized by another remark by Churchill: "How does your chief feel about an alliance between your country, France and England?" Hanfstaengl wrote that he was "transfixed" at this. (Remember, Hitler had not yet come to power; the quote sheds interesting light on Churchill's thinking at the time, already intent on preventing another war by a coalition that would presumably redress Germany's legitimate grievances over the Versailles Treaty.)
In a last-ditch attempt to get Hitler to change his mind and meet Churchill, Hanfstaengl excused himself and went in search of Hitler, finding him in the stairway of his apartment "in a dirty white overcoat, just saying good-bye to a Dutchman...'Herr Hitler...don't you realise the Churchills are sitting in the restaurant?...They are expecting you for coffee and will think this a deliberate insult.'" Hitler said he was unshaven and had too much to do. Hanfstaengl suggested he shave and come anyway. Hanfstaengl then returned to the Hotel and played the piano for the Churchills, hoping Hitler would arrive, but he never turned up.