Balsamic-marinated red onions, chopped fine, provide an almost meaty note to the salad.

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Slices of juicy porchetta were, in midsummer, accompanied by a bright palette of grilled peaches, pickled red onions, and a fresh-herb salad.

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Haywards dates back to 1868 and also makes pickled onions red cabbage and gherkins.

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Red or sweet onions, mango or watermelon, any fruit or vegetable that you think would go well in your ceviche probably will.

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But apples contain high levels of an antioxidant flavonoid called quercetin which is also found abundantly in onions, tea and red wine, and may be important in protecting the lungs from the harmful effects of atmospheric pollutants and cigarette smoke.

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Theirs comes with duck confit, caramelised balsamic onions and a foie gras and red wine sauce.

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Plump red pumpkins and squashes called kadhoos are pan-cooked with onions or transformed into halwa, a warm, melt-in-your-mouth dessert with the consistency of fudge.

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