Any pro or amateur chefs out there have an idea for what to substitute for mustard? I have a friend who is 911 peanut allergy level allergic to it in any form (powder, seed, prepared, etc.). Most of the time I can work around it but it seems like so much BBQ stuff revolves around using it in some way whether it's slathering mustard on the meat before smoking or cooking it or using it in BBQ sauces or in rubs.