Use a spotlessly clean bowl (wiped with lemon juice to completely degrease) for the egg whites.
Very carefully crack the eggs and separate the whites from the yolks, being super-careful not to get ANY yolk in with the whites.
Take the bowl of whites and either loosely cover with a cloth or kitchen towel or with clingfilm that has had a few holes pierced in the top.
Leave the egg whites at room temperature for a few hours before using.
Save the yolks to use in another recipe or make an enriched omelette/scrambled egg/frittata.
Prepare 2 or 3 large baking sheets by lining with good quality non-stick baking paper.
Either trace circles about 3½ cm (1½ inches) in diameter onto the baking paper, with a gap between each (flipping the paper over onto the baking sheet so that the drawn side is underneath), OR use a printed macaron template that can be placed under the baking paper whilst you pipe (remembering to remove before baking).
Make sure your mixing bowl and balloon whisk head for the egg whites are spotlessly clean and grease-free. I wash mine in very hot water with soap, then allow to air-dry, before wiping again (using clean kitchen paper) with a solution of hot water and lemon juice.
Prepare a disposable piping bag by either snipping the end to make a hole about 1½ cm in diameter, or by inserting a round nozzle (approx. 1.6 cm).
Attach a food-bag clip just above the nozzle/end, to prevent the mixture leaking out when you fill the bag.
To make the Macaron Shell batter
Weigh the ground almonds and icing sugar into a blender and pulse for a few seconds to blend and grind the almonds very slightly finer. Be careful not to over-blend as the almonds will turn to almond butter. Set aside.
Weigh 110g aged egg whites (that must be room-temperature) into the bowl of the mixer.
Start to whisk slowly until bubbles start to form and the egg whites become foamy.
Add the cream of tartar and increase the speed of the mixer to high.
Little by little, add the granulated sugar, whisking continually until all the sugar is incorporated and dissolved.
Whisk until the mixture has become thick and glossy with stiff peaks. But be careful not to over-mix as this will make the egg whites dry and brittle.
Add the almond-icing sugar mixture along with the orange extract and a little food colour and very gently fold into the egg whites using a large spatula-spoon or spatula.
Continue to gently fold until the dry ingredients are incorporated and until the mixture reaches a ‘molten lava’ consistency (when it leaves a ribbon trail that takes about 20 seconds to sink back into the mix). Be very careful not to over-mix.
Pipe the macaron
Transfer the mixture to the prepared, clipped piping bag.
When ready to pipe, remove the clip and pipe straight down at a right angle onto the templated circles, until it almost reaches the border.
When you have finished, carefully remove any paper templates from underneath the baking paper.
Take each baking sheet in turn and hold evenly about 12 cm (5 inches) above the work top or a hard kitchen floor. Flat-drop the tray several times, to bang out any air bubbles.
Leave the trays at room temperature for between 30 minutes and an hour, to allow the batter to dry slightly and until a skin forms. This is super-important. You will know they are done, when you lightly touch the edges and they are no longer sticky.
Bake the macaron
Preheat the oven to 150 C (130 Fan)/300 F/Gas 2.
Bake one sheet at a time (adjusting times/temperature from your experience on the first batch).
Bake times will vary from 11 to 15 minutes for small macaron.
When done, the macaron should have a dry, slightly shiny top and the shell should be reasonably firm and not wobble when pressed. The bottoms should not be wet.
Take out of the oven and allow to cool on the trays before carefully lifting off the baking paper.
Make the ganache
While the macaron are cooling, make the ganache.
Chop the chocolate into small pieces and place in a heat proof bowl.
Heat the cream in a saucepan until it is just beginning to start to simmer.
Immediately remove from the heat and pour over the chocolate.
Push the chocolate down so that it is under the surface of the cream and tilt the bowl back and forth to allow the hot cream to seep into the cracks.
Cover the bowl with a plate to keep the heat in and leave to sit for 5 minutes.
Now gently stir until the chocolate has completely melted and the ganache mixture is smooth. If any lumps of chocolate remain, place the bowl over a saucepan with a small amount of simmering water and gently heat and stir until smooth.
Leave the ganache at room temperature to cool and thicken to soft piping consistency.
Fill the macaron
While the ganache is cooling, pair up equal-sized macaron shells in a row on the work surface - one top side up and one top side down.
When the ganache has reached piping consistency, transfer to a piping bag fitted with a 1.6 cm nozzle or snip off the end.
Pipe a good-sized blob of ganache into the centre of each of the flat-facing macaron shells and sandwich with the second shell, gently squeezing together until the filling can be seen at the edge.
Store in an airtight container in the fridge until ready to use/eat.
* Note: nutritional information is an estimate & may vary according to portion size/ingredient variants.I do not advise using egg whites from a carton as many add guar gum and other thickeners which can ruin the macaron batter. If using carton egg whites, only use those which contain no other ingredients.