Preheat oven to 180° C (350° F).Prepare muffin tin or if using a cake tin, grease and line the base with baking parchment. An 18cm/7 inch round tin is about right.
Using a fine grater, grate the rind from the two clementines and add to the caster sugar. If you want to intensify the orange flavour a bit more – you can whizz the sugar and zest a couple of times in a food processor to release the oils but no harm done if you miss this step.
In a bowl, cream together the butter, sugar, and clementine rind until pale and fluffy. Gradually add the beaten eggs to the mixture, beating well after each addition. Gently fold in the self-raising flour, followed by the ground almonds and the cream.
Spoon the mixture into the muffin cases or prepared tin.Bake for 30 minutes (muffin size) or 55 – 60 minutes for a large cake, or until a fine skewer comes out clean.
Leave to cool slightly.
Meanwhile, make the glaze: Put the clementine juice into a small saucepan with the caster sugar. Bring to the boil, then reduce the heat and simmer for 5 minutes. In another pot or in the microwave, melt the chocolate until liquid. Brush the sugar glaze over the cakes until it has been fully absorbed. With a little tooth pick draw a pattern with the chocolate.