Preheat grill to high + oil grates; cut off the stem of 1 onion, discard outer skin, then carefully slice onion into ¼ to ½-inch rounds; drizzle with oil + salt/pep; grill 5 min with lid closed, flip + grill 4-6 min until charred + slightly softened

Season burgers with salt/pep + rub with 1 tbsp oil then add to grill; cook with lid closed for 6 min, flipping halfway, until cooked through

Grill 2 buns until warm + golden; spread each bun with mayo then top with burgers + onions, chef era unlocked!