This is a very simple dessert to prepare and you will need 4 jars or glasses. Place the defrosted raspberries, sugar and lemon zest into a pan and cook down for 10-15 minutes with a drop of water. Allow to cool down completely. Next, cut the sponge to fit into the bottom of your glasses and place in. Spoon over a little of the cooked raspberry jam, followed by a few fresh raspberries. Next, mix together the yogurt and lemon curd, then fold in the remaining raspberry jam but don’t mix completely so it looks marbled. Spoon this mixture over the sponge and raspberries and refrigerate for 30 minutes to set. When ready, top with the remaining fresh raspberries and serve.