Boil your potato (skin on) until it is tender. Remove the skin and mash the potato until it is smooth, with no lumps. Allow to cool completely.
Once your mashed potato has cooled completely, add the icing sugar a spoonful at a time, mixing each spoonful before adding the next. The potato mixture will become watery before it thickens again - this is ok!Continue to add and mix the icing sugar until your have a thick, fondant texture. You may need more/less icing sugar, depending on your potato. Line a couple of baking sheets with some greaseproof paper. Set aside. Take a large teaspoon of your fondant and roll it in your hands to create a small ball. Place onto your lined baking sheet. Repeat with the rest of the fondant.Let the fondant balls sit for a few hours, or overnight; lightly covered with some greaseproof paper. This lets them dry out and harden a little. Alternatively, if you are tight on time, you can place them in the freezer for an hour.
To prepare the coconut, sprinkle half the desiccated coconut onto a small baking tray. Place this under a warm grill for a few minutes, keeping a close eye that it doesn't burn - you just want it to catch a bit of warmth and colour. Remove the coconut from the grill and mix it with the remaining un-toasted coconut.
One your fondant balls are ready, melt your chocolate over a bain-marie or in short blasts in a microwave.
Set yourself up with a production line of fondant balls, melted chocolate and coconut.First, dip your fondant into the chocolate, ensuring it is well coated. Allow the excess to drip off (scooping it out with a fork is good for this).Next, drop it into your coconut, again making sure it is well coated.Then place back onto the lined baking sheet. Repeat with the rest of the fondant balls.
Pop your coated Macaroons into the fridge to allow the chocolate to set, before enjoying. Macaroons keep well in to a air-tight Tupperware.