Preheat your oven to 200ºC/400ºF/gas 6. Firstly zest 3 of your oranges, then carefully remove the outer peel and slice them across into wheel-shaped pieces just under 1cm-inch thick. Break the dark chocolate up, place in a small bowl and slowly melt it over some simmering water, giving it a stir once in a while with a spatula.
You will need a deep 20cm metal tin or earthenware dish to cook the clafoutis in. Rub the inside of it with a little of the butter. To make the clafoutis, sift the flour into a separate bowl, add the almonds, half the sugar, the salt, eggs, yolks, orange zest and milk. Whisk up until smooth and then add the rest of the butter to the melting chocolate. Scrape all the melted chocolate and butter into the batter mix and pour into your tin. Poke little pieces of white chocolate into the batter, then place the tin in the oven and bake for around 16 to 20 minutes. It will rise and should be firm around the edges but sticky and gooey in the middle. This doesn’t mean it’s undercooked... it means it’s perfect! So be careful not to overcook it or it will just be like a boring sponge.
While it’s cooking, bring the other half of your sugar to the boil with about 6 tablespoons of water on a medium heat until you have a golden caramel. Remove from the heat, add the juice from your remaining oranges and stir it in to loosen the caramel syrup slightly. Arrange your oranges nicely on a plate, pour over the caramel and serve with your chocolate clafoutis and, if using, a bowl of crème fraîche.
• adapted from Jamie's Dinners