Grind almonds 2 or 3 times.
Beat egg whites with salt until foamy but not too stiff. Stir in the sugar gradually so it is well blended. Add the ground almonds, mix and knead well until creamy and smooth. If the paste seems too stiff, add a few drops lemon juice, one drop at a time until paste seems right to form into shapes. If it gets too thin, add more sugar.
Pack the mixture in a container with a cover and let rest in a cool place for at least 2 days to ripen. Shape into balls or other forms and roll in powdered sugar. It may also be rolled into small jelly-roll shapes and sliced.
Let stand overnight to form a crust if you would like to paint your shapes with food colorings to resemble strawberries, bananas, oranges, apricots, carrots, potatoes, etc. Use your own imagination to improvise stems and leaves when you need them.