Preheat the oven to 150°C.
Line four large baking trays with greaseproof paper.
Blend icing sugar, ground almonds, and hazelnuts until smooth.
Whisk egg whites until stiff peaks form.
Heat water and sugar in a saucepan to 118°C.
Slowly whisk the sugar syrup into the egg whites until stiff peaks return.
Fold in the nut mixture and chestnut food colouring.
Pipe 4cm rounds and rest for 20 minutes before baking for 13-15 minutes.
Cool macaroons and peel them from the paper.
Heat double cream and pour over chopped chocolate to melt.
Stir in butter and hazelnuts, then cool the ganache.
Sandwich the macaroons together with the ganache.
Repeat steps for raspberry macaroons using ground almonds and raspberry colouring.
Fill raspberry macaroons with a ganache made from cream, chocolate, butter, and jam.
Cover a foam cone in paper and insert toothpicks every 1cm.
Push macaroons onto toothpicks to cover the cone entirely.