Preheat the oven to fan 160C/extinct 180C/gasoline 4. Thinly reduce the unpeeled oranges then attach them in a saucepan with 400ml/14fl ounceswater and the sugar. Disappear everything around and poach the oranges, covered, over a medium warmth for 20 minutes unless the pith feels gentle when tested with a keen knife. Exhaust from the warmth and streak away to chill.
Grease and line a 20cm springform cake tin and location up the nicest poached orange slices (about seven) in the bottom. Pressure the rest orange slices, maintaining the poaching liquid. Purée 100g/4oz of the oranges along with 75ml/21⁄2 fl ouncesof the liquid, to make a delicate combination (a hand blender is reliable for this).
To make the cake, combine the flour, baking powder, almonds and poppy seeds collectively and fasten aside. Trot the eggs with the caster sugar unless the aggregate seems to be esteem softly whipped cream. This could merely buy 5-7 minutes. Without extend fold in the orange purée very gently the exhaust of a spatula, so that you just don’t knock out your total air.
Fold the dry substances into the foamy orange combine, stopping as shortly because it’s mixed. Fastidiously pour the aggregate into the ready tin and bake for 40-Forty five minutes unless golden brown and springy to the touch. Test with a skewer – if it comes out trim from the centre, the cake is cooked. Exhaust from the oven and streak away to chill in the tin. When frigid, flip the cake out so the orange slices are uppermost.
While the cake is cooling, make the curd. Beat the eggs with the orange and lemon juices, then stress correct into a bowl. Add the sugar, butter and orange and lemon zest, then self-discipline the bowl over a pan one-third beefy of boiling water. Disappear over the warmth unless the aggregate thickens – it’s ready when it thickly coats the help of your spoon (this can also buy in to half-hour, so be affected person). Trot away to chill.
Within the reduction of the cake all the procedure by twice, into three sections. Brush center and bottom layers with a few of the leftover syrup. Divide the curd between the layers and unfold it out, then sandwich all three sections collectively. Brush the tip with more syrup. Let the cake sit down for a pair of hours to enable flavours to build. It retains for 3-4 days in the fridge