YUM! I really liked this quesadilla. I wasn't sure of the dry mustard but I really couldn't tell it was in there. This is a very delicious and different take on a tuna melt. Thanks for sharing the recipe! Made for Bargain Basement Tag.
I made this today in my small Foreman grill. It was easy but I won't rate it since I'm not a tuna lover and I made some changes due to preference and necessity. Hubby's was made with vegan mozzarella but I didn't taste it. I chose cheddar. Also omitted the onions but added chopped olives. It was just OK for me. Since tuna isn't a fave...I'll keep looking for something with more seasonings that hide the flavor!