Preheat the oven to 160°C.
Split the vanilla pods in half, scrape out the seeds and sift with the ground almonds and the icing sugar.
Whisk the egg whites until stiff. Add the caster sugar to the the egg whites and continue whisking until you have stiff, glossy peaks of meringue.
Fold the ground almonds, vanilla and icing sugar into the meringue mixture. Cut and fold the mixture with a spatula until it is smooth, shiny and has reached the ribbon stage.
Use a piping bag to pipe this mixture on to a baking mat or lined baking tray. Allow the macaroons to rest at room temperature for 10-15 minutes until the macaroon shells are no longer sticky to touch. Bake in the oven for about 10 minutes. Allow to cool before filling.
Place the remaining 170g sugar in a heavy bottomed pan and allow to melt, without stirring, to a golden caramel. Add the butter, the chocolate, the salt and the cream and mix well. Once well combined, remove from the pan allow to cool.
Once cool, transfer the filling to a piping bag and then pipe on to half of the macaroon shells.
Cover half of the macaroon shells with the caramel filling and then top with a second macaroon shell. Sandwich the macaroons together to serve.
«The temperature of 150'C is based on using a fan assisted oven. If you do not have a fan assisted oven, preheat the oven to 160'C.»