Sieve or sift the icing sugar and ground almonds together into a large mixing bowl. Throw any lumps left behind away. (The bigger pieces makes the Macarons lumpy and cracked during baking) whisk with electric mixer, the egg whites and salt until they form soft peaks (making sure utensils are grease free). Add the caster / fine sugar, a little at a time and continue to beat ( you can add the colouring at this time. Add a bit more colour to make the Macarons vibrant. It loses some colour during baking) until the whites are very thick and glossy (ideally, you should be able to hold the bowl upside down without the whites falling out! About 10 mins on high speed) Gently fold in the icing sugar and almond mix. (About 40-50 folds) The mixture will now be loose and semi-runny. Using a piping bag with a 1cm / 1/3" nozzle, fill with the macaron mixture. Line baking sheet with silicone mat or parchment. Pipe small blobs about 2 inches apart from each other. Gently tap the baking sheet a fe

Tips and tricks: 1) make sure the eggs are room temperature. (Out if fridge for at least 2 hours) And not freshly bought. Older egg whites work great. If you forgot to take the eggs out, you can put them in warm to medium hot tap water for about 5 mins. 2) use a steel bowl to whip. And make sure it is scrupulously clean before use. Any oil will deflate the egg whites. 3) you can make your own almond flour by buying raw slivered almonds and pulverizing them in a blender. 4) folding is very important part. Over mixing will cause the Macarons to spread out and be flat. Under mixing will cause the tops to crack and be hollow inside. It takes practice to get the right consistency. I would say viscous enough that it runs off the spatula, but still hold a shape for a 5 seconds when dripped down. 5) no oil food coloring. Gel and powder work wonders. The more vibrant the colour, the more fun! 6) I wouldn't necessarily add any flavoring to the Macarons. I would flavor them by using different