Preheat oven to 375F/190C.

Dice onion. Make foil packet and throw onions and chicken in there. Drizzle olive oil & 1/2 tbsp of bbq over chicken & onions.

Fold packet up & cook 20-25 mins. Scope things out and make sure the chicken is cooked all the way through.

Toast bagels (light-to-medium) in toaster oven/toaster.

Remove chicken, let it moderately cool, then dice/chop. I patted mine down with a paper towel first. Drain onions from the packet.

Smear 3 tbsp of BBQ sauce on the toasted bagels.

Layer a bit of cheese, then chicken + onion + toppings, and top with remaining cheese.

Pop under the broiler in your oven or toaster over til it’s all melty and delicious.

Drizzle with the remaining 1-1.5 tbsp of bbq sauce