Preheat the oven to 155'C.
Sift the ground almonds and the icing sugar together.
Whisk the egg whites until white and fluffy and then add the caster sugar to the egg whites and continue whisking until you have stiff, glossy peaks.
Fold the ground almonds and icing sugar into the meringue mixture.
Cut and fold the mixture with a spatula until all of the dry ingredients are incorporated and the mixture is smooth, shiny and has reached the ribbon stage.
Carefully add the food colouring making sure not to overwork the mixture. Spoon the mixture into a piping bag.
Pipe 2cm circles in straight lines across a baking sheet lined with a silicon paper. Leave a 1 cm gap between each macaroon shell. Drop the tray of macaroons onto the work surface from about 30 cm to remove any large air bubbles.
Allow the macaroons to rest at room temperature for 20 minutes or until the macaroon shells are no longer sticky to touch.
Bake in the oven for 15 minutes. If you are baking lots of macaroons you may need to keep the oven door slightly ajar (with a spoon or paper) to prevent steam building up in the oven. After 15 minutes, check the macaroons are cooked by gently lifting a macaroon at the edge of a tray. If the test macaroon does not stick, allow the tray of macaroons to finish cooking on the tray as it cools.
Allow the macaroons to cool completely before filling.
Bring the butter to room temperature. Sieve the icing sugar and beat in with butter. Then add the rum and mix through the butter cream.
Place the raisins, rum, cinnamon and the caster sugar in a saucepan. Place the pan onto the heat and bring to the boil. Once boiling, reduce the heat and cook gently until all of the liquid has evaporated and been absorbed by the raisins.
Allow the macaroon shells to cool completely before filling.
Fill half of the macaroon shells with the buttercream and place two raisins in the centre of the buttercream and then top with a second macaroon shell.
«When making this recipe, add some mixed peel to the pan of raisins to add a citrus note.»