Preheat the oven to 180'C.
Mix the baking powder through the flour and sift into a large bowl. Zest the orange and juice one half.
Cream the sugar and the butter together until pale and fluffy. Add the eggs to the mixture one by one, beating each one in before adding another. Fold in the poppy seeds, the orange juice and zest and the sifted flour.
Pour the cake batter into individual moulds and bake for 20 minutes.
Cut the butter into cubes. Zest and squeeze the lemon juice.
Add the butter, icing sugar, zest and the juice of the lemon and the butter to a saucepan. Cook over a low heat until the butter has melted. Add the egg yolks and whisk until the sauce begins to thicken. Pour into a flat fish and leave to cool.
Whip the cream to soft peaks and then fold in the cooled lemon curd to make the mousse.
Squeeze the juice from the orange and add the icing sugar. Mix until lump free and then bring to boil to thicken the syrup.
Place the cakes on individual serving plates. Drizzle the orange sauce over each cake and then spoon the lemon curd mousse on top. Dust with icing sugar to serve.
«Check that the cakes are cooked using a skewer or the tip of a sharp knife.»