It takes a while, but over about a year I have trimmed down quite a bit by just eating less of everything, I don't, therefore, feel deprived and can't face a large plateful now. I don't like cornflakes, muesli etc., but OH does, with half a banana sliced on top.
As a result, my breakfast is half a grapefruit, followed by natural, live yoghurt accompanied by the other half of the banana and 2 mugs of tea, milk, no sugar. The banana gives me some healthy carbs., the grapefruit vits. and roughage and the yog. calcium and healthy bacteria. Suits me. I can't stand croissants (having lived all those years in France!). Don't know if this helps, it's a lot of weight to shift fast, depends on your age. I could have done it by drastic dieting 25 years ago, but it gets harder. Increase your exercise if you can. Good luck. :)