Ya'll got to try this if you like burgers and onions, my simple grilled onion burger recipe..............................
I cut slices of Vidalia onions, about 3/4 to an inch thick. If you carefully slice out the center of them the outside ring is curved in on top/bottom and holds the whole slice together when you turn them over. I'll also grill the top/bottom slices but they will often fall apart when turning, still good but a solid, center coin of thick onion is better on the finished burger.
I pour EVOO on a plate and flip the onion slices in the oil coating them w the oil while also seasoning them w Janes Crazy Mixed Up Salt.
I add or pour some more oil on the plate/onion if the onions soak it up off the plate.
let them marinate a while in the oil/spices (or while I get the grill and hamburger/deerburgers ready)
Grill the fat slices of onion w the burgers about 10 mins. a side, turning the onions once carefully to keep them intact , sometimes I put the onions on first for 5 mins. or so , then move them to the edges of the grill to make room for the burgers.
When they're soft and slightly charred I take the onions off the grill.
When the burgers are done (M rare for me) I put the burger ( or cheeseburger, Provolone works well for this ) on a bun, add a fat slice of grilled onion, mayonnaise and black pepper, that's it.
It makes a sloppy, hard to hold/eat burger but they are different from the typical burger and very tasty. Kinda like a grilled Philly cheese steak on a hamburger bun.
EDIT. These onion burgers are also very good a bit of thick BBQ sauce brushed on the burgers right after flipping them, then melting pepperjack cheese on them and hold the mayo.