Insults

What is the most effective way to insult a group of young Muslims? Perhaps serve them pork and then bring up the subject of Isreal.
During lunchtime the other day a group of three young men dressed in suits came into the Thai restaurant. I took their order and then brought them their complementary wonton soup. As I was setting the soup on the table one asked me, "what kind of meat is the soup made with?" "Pork, I think, but let me check with the kitchen," I responded. The three gentlemen began to wave off the soup with vigor saying, "no, no, no, we don't want any." I quickly came to the conclusion that they were Muslims and began going over their order in my head to be sure that there would not be pork in any of the dishes that they had ordered.
Another young man in a pin striped suit joined the group of three. I asked him what I could get him to drink and he held his throat and said, "I have a cold, what kind of tea do you have?" I told him we only had Chinese Jasmine tea. He asked "d'you have any jus'regul tea?" I responded according to what I thought I had heard, "What, you want Isreali tea?" He spoke louder and enunciated more clearly "No, I said REGULAR tea." "Ohhh, no, sorry, only Jasmine" I responded.
I went in the back to fetch his tea and began to reseign myself to the fact that I would be getting no tip from the gentleman after having offered them pork and then brought up Isreal out of the blue. But I guess being a young woman serving a table of young men trumphs all political and religious faux-pas. They left a hell of a tip.