2 medium yellow onions
1. Remove the skin from the onions and slice them into rounds 1/2-inch thick. Try not to allow the rings to separate from the rounds - they will be easier to work with if they remain intact.
2. If grilling:
- Lay the rounds in a single layer on a large pan or plate and brush them with olive oil. Turn them over and brush the other side as well.
- Set up your grill for medium direct heat. When hot, brush and oil the grate. (Oiling the grate helps make sure the food won't stick to it. We dip a wad of paper towel in flavorless high-heat oil such as canola, and, wearing oven mitts, use long tongs to brush it against the top of the grate. Careful - if the oil is dripping, the fire may flame up dangerously as you do this! Move quickly and keep your distance to do this safely.)
- When the hot grate has been oiled, use long tongs to place each round on the grill, careful not to allow them to fall through. Close the lid and allow the onions to cook for about 6-8 minutes.
- By this time, the onions should be getting soft and the bottoms should be browning. If so, carefully turn them over (if not, let them cook for another 2-3 minutes first). Let the onions cook on the second side until they are quite soft and caramel-brown in color, about 6-10 minutes more (depending on the heat of your grill).
3. Or, if broiling:
- Set up a pan to broil the onions on: a shallow pan such as a broiler pan or a rimmed cookie sheet works best here. We like to line it with aluminum foil to make cleanup easier.
- Make sure the oven rack is positioned near the broiler and preheat your broiler to high.
- Lay the rounds in a single layer on the foil-lined pan and brush them with olive oil.
- Slide the pan into the broiler and broil for about 7-9 minutes. When the onions are starting to get soft and brown, turn them over and broil for about 6-10 minutes more, until they are quite soft and caramel-brown in color. If at any time the onions seem to be getting crispy-black instead of soft and brown, you may need to move the oven rack farther away from the heat.
4. Transfer the onions to a serving plate, allowing the rounds to separate and arrange themselves in a pleasantly chaotic mound. Remove any crispy, over-browned pieces before serving.