“I didn’t want to put ‘terrorist’ on the board, so we were going to put ‘Muslim extremist,’ but we didn’t have room on the board,”
Because terrorist was bad and you ran out of room? I’d argue that the reaction to “terrorist” would be less. Yeah, some might not be happy by it, but just go ahead and appear to hate an entire religion while thinking that we can all read your mind that you wanted to add the word “extremist” but your sign board was too small.
Maybe remove “Food Ice Cream” because you are a restaurant. I expect you to sell food. Then you can add extremist.