Preheat oven to 160c and line two large baking sheets with greeseproof paper.
In an electric mixer, whisk the egg whites until fluffy.
Add the sugar and whisk on high speed until a solid soft to firm peak is achieved.
Gently fold in the ground almonds until incorporated.
Spoon the mixture onto the prepared trays to form little balls. (My baking sheets hold five rows of four little balls, approximately 1.5inches in diameter.) If you want to garnish with flaked almonds, allow to sit out for 15 mins prior to placing the almonds on top - this will prevent the almond sinking. When making for the kids, I skip this bit as it makes it much quicker.
Place in the oven and bake for 12-15 minutes or until golden.