If using whole almonds , keep them in boiling water for 5 minutes , slip the skins off and dry completely. In a blender or food processor , pulse it with the icing sugar until a fine powder is formed .
Mix the egg whites with the salt / lemon juice with the water. Keep aside.
Food processor method : sift the icing sugar and ground almonds. Run it in the processor and pour the egg white ( or lemon juice-water) and extract slowly in . Process until a smooth dough forms.
By hand : sift together the ground almonds and icing sugar mixture. Add the egg white (or lemon juice -water) and extract and mix until a rough dough forms. Knead for few minutes (adding a little icing sugar if it gets sticky ) until a smooth dough forms.
To colour , add a drop of gel food colour and knead until colour is uniformly distributed . Add more colour and knead as needed.
Wrap in plastic wrap well and refrigerate for few hours before using.