I took the onion off and made some garlic bread with the loaf so things turned out okay.
I was looking forward to the BLT though.
Edit: I ordered delivery through GrubHub, so I couldn't see them making the sandwich. I thought it seemed a little light when I took it out of the bag, but the BLTs I've gotten before have always felt light, so I didn't realize.
Also this is c/mildlyinfuriating. It wasn't a huge deal, and GrubHub refunded me for the item, but it was mildly infuriating since I wanted a BLT and someone misunderstood my order.