Well, they’re actually roasted, but you get the same effect without having to stand over them.
They are particularly lovely served with sausages and mash or for steak and onions.
This recipe is from Delia's Complete How to Cook. Serves 2
First of all you need to cut the onions into ¼ inch (5 mm) slices, then place them in a bowl, add the oil and sugar and toss the onions around to get the lightest coating.
Then spread them out on a baking tray and place on a high shelf of the oven for 14-15 minutes – they need to be nicely blackened round the edges. You can also watch how to chop onions in our Cookery School Video on the right