Servings: Serves 8
Ingredients 3 red onions , cut into 1/4-inch slices3 yellow onions , cut into 1/4-inch slices1/4 cup extra-virgin olive oil3 tablespoons balsamic vinegar1 teaspoon salt1/2 teaspoon freshly ground pepper
Combine all ingredients and divide between 2 shallow pans. Allow to sit at room temperature 30 minutes to 1 hour.
Place the onion slices on grill (flame should be low) by using a vegetable tray or by laying directly on grill (be careful not to let them fall through; rings will break up). Turn once or twice until tender; grill about 20 to 30 minutes.