I've been working on this recipe recently trying to get the quantities just right, the shells have a delicate mint flavour while the chocolate ganache is intensely rich. I recommend serving them with coffee at the end of a meal or between courses as a sweet palate cleanser.
You will need:
For the shells:
2 large eggs
60g ground almonds
110g confectioners' sugar (icing sugar)
20g castor sugar
1 1/2 teaspoon peppermint extract
Green food colouring
For the dark chocolate ganache:
60g of dark chocolate
2 tablespoons salted butter
2 tablespoons whipping cream
This part is really important. Separate the egg whites from the yolk and keep them in the fridge for up to 24 hours. After 12 hours you can start to make macaroons. I can't tell you exactly why resting the egg whites makes better macaroons but it does so… there you go. Bring the egg whites to room temperature before continuing. You can buy egg whites at your local store if this is more convenient for you.
Preheat your oven to 150ºC (300ºF).
Put the confectioners' sugar and ground almonds into a blender and grind them into a fine powder. Strain this mixture through a sieve onto a baking tray and bake in the oven for 5 to 7 minutes. Don't try and push the mix that doesn't go through the sieve through with a spoon, just discard it. Allow it to cool.
Beat the egg whites in a bowl until they start to form soft peaks, using an electric hand whisk speeds this process considerably. When the peaks start to stiffen gradually add the castor sugar continuing to beat the egg whites constantly. Add a few drops of the green food colouring, some bakers suggest using a gel colour as it's less likely to destabilize the egg whites at this stage. I haven't had a problem with this as I only add two to three drops of food colouring at most.
Sieve the cooled sugar and almond mix onto the now green, stiff egg whites and gently fold it in. Using a silicone spatula gently work the mix in a figure of eight motion until it is smooth. When you pipe the mix onto a prepared baking tray any peaks should sink so each shell is flat. If the peaks do not sink you need to work the mixture more until the consistency is smoother. Be careful not to overwork it though as this will knock all the air out of the egg whites and the macaroon shells will not rise.
Pipe circles of the mixture onto a baking tray prepared with parchment paper. Try to keep the circles as uniform as possible and leave at least 1cm between the shells as they will spread slightly. Now gently but firmly tap the baking tray on a flat surface to release any air bubbles. Failing to do this can lead to total macaroon failure.
Allow the macaroons to rest for at least an hour or until a crust has formed over the top, then bake for 12 to 15 minutes. Keep an eye on your macaroons after the 10 minute mark, they can go from perfect to disaster ever so quickly. Allow the macaroons to cool before attempting to lift them from the baking tray. If they won't separate from the parchment paper trickle a little water between the tray and the paper (not the paper and the macaroons). Use a thin icing spatula to lift them off if necessary.
Make the chocolate ganache the same way as in this recipe for milk chocolate and vanilla macaroons substituting dark chocolate for milk chocolate and omitting the vanilla seeds.
Create a bain marie, break the chocolate into small pieces and melt it slowly. Add the butter allow it to melt while gently stirring the mixture, then add the cream continuing to stir. Remove from the heat and allow to cool before chilling the ganache in the fridge.
Spread or pipe the ganache over half the shells and sandwich with a matching top. Chill for 1 hour before serving. Enjoy...