Where there's a will, there's a whey: Yotam Ottolenghi's ricotta recipes

Not only is ricotta an ingenious way of using up something that would otherwise go to waste, it's also incredibly delicate and delicious Yotam Ottolenghi's ricotta and oregano meatballs: 'The younger and fresher your ricotta, the less you have to do to enjoy it.' Photograph: Colin Campbell for the Guardian One man's trash is another man's treasure; and the by-product from one food can be perfect for making another. Ricotta is not so much a cheese as the leftovers after the curds have been strained to make other cheeses. The whey is cooked again – ricotta means, literally, "recooked"– with sour whey or another coagulant. Not only is this an ingenious way of using up something that...