Nacho Mama's has very tasty grilled cheese sandwiches and they are very careful about cross contamination when you order a gluten free item. I believe the owner doesn't eat gluten, so she's very aware. They also have nachos and quesadillas. The only downside is that their hours are very limited, as Nacho Mama's is a food truck that is only open for a couple hours most days. It's worth checking their schedule (which is on their website; I will link it here) and seeking them out when they're parked somewhere around the Peoria, IL area.