Start by holding a sweet onion on a cutting board, ensuring the root end is facing sideways. About 3/4 of an inch from the root, take a wooden skewer and drive it through the center of the onion. This skewer serves as a guide to slice evenly.
With the skewer in place, slice off the root end of the onion on one side. On the other side, make a cut, ensuring about 3/4 inch of onion remains on the skewer. This technique helps keep the slices uniform.
Carefully cut the remaining part of the skewer that is sticking out of the onion. Repeat this process for the second onion, ensuring you have two skewered onions ready for grilling.
Next, brush both sides of the onion slices with olive oil. This not only adds flavor but also aids in achieving that crispy exterior.
Sprinkle kosher salt and fresh ground pepper over the onions, seasoning them to bring out their natural sweetness.
Prepare your grill for two-zone cooking: coals on one side and no coals on the other. This method allows for indirect grilling, which is crucial for even cooking.
Place the onions on the cool side of the grill, turning them every 10 to 15 minutes. Keep an eye on them until they become golden brown and tender, which typically takes 25 to 40 minutes, depending on the grill's heat.
For gas grills, preheat by heating for 5 to 10 minutes. Then, lower the burners to low and place the onions on the low burner. Flip them every 10 minutes until they achieve that beautiful golden brown color.
Once caramelized and tender, carefully remove the onions from the grill, and let them rest for a few minutes before serving. This resting time allows the flavors to develop even further.
