Sift the almond flour and icing sugar. Set aside.
Mix the egg white A with the almond flour mix until you get a paste. Do not overmix. Keep covered with plastic wrap to prevent the top from drying.
Combine the granulated white sugar with water in a saucepan and place over heat.
Meanwhile, whisk egg white B until foamy. When the sugar syrup reaches 119°C, slowly pour it in a thin stream over the egg white while continuously mixing. Whisk until you obtain a glossy and firm meringue. Add the food coloring and mix well.
Incorporate 1 tablespoon of the meringue into the paste, then fold in the rest of the meringue. Mix gently until you achieve a batter that is thick but flows off the spoon or spatula in a ribbon.
Transfer the batter into a piping bag fitted with an 8-9mm round tip, then pipe the macaron shells onto a silicone mat or parchment paper.
Tap the tray gently on the work surface to release any air bubbles, then let the macarons dry at room temperature for 10-30 minutes, depending on the room's temperature and humidity. You'll know they are ready to bake when the surface has formed a crust that doesn’t stick or break when touched.
Bake in a preheated oven at 130°C with fan on for 15-20 minutes.
Once done, remove from the oven and let cool on the tray.