Subscribe to our magazine
Save 42% & receive a £10 M&S e-gift card!
Heat oven to 200C/180C fan/gas 6. Put the flour in a large sealable plastic bag. Season, then tip in the onion and shake well. Whisk the egg whites until foamy, add the onions and stir to coat.
Lightly oil a baking sheet. Add the seasoning and breadcrumbs to the bag; then, working in batches, add the eggy onion rings and coat in the crumbs. Arrange onion rings, in a single layer, on the baking sheet and cook for 25-30 mins, turning halfway through, until the onion is tender and the crumbs are golden.