At the end of their wine-and-cheese parties, cheese experts Helen Jane Hearn and Natalie Wassum gather any leftovers to make this incredible mac and cheese later in the week. Preheat the broiler.

Arrange 6 tortillas on 2 large baking sheets. Spoon the onions onto the tortillas and top with the shredded chicken and blue cheese. Cover with the remaining tortillas, pressing to flatten slightly.