Raspberry ricotta cake

Fruit and vegetables

1 lemon, lime, grapefruit or orange, zest only (optional)

340gâ€“450g/12ozâ€“1lb raspberries, fresh or frozen

Tins, packets and jars

220g/8oz plain flour

Cooking ingredients

1 tbsp baking powder

275g/9Â¾oz caster sugar

Â½ tsp vanilla extract

Dairy, eggs and chilled

115g/4oz unsalted butter, melted

3 large free-range eggs

365g/12Â½oz ricotta, plus 400g/14oz to serve

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