Preheat the oven to160ºC (325ºF). Line two baking sheets.

In a large bowl, mix together the ground almonds and sugar. In a separate bowl, whisk the egg whites with a pinch of salt until they form soft peaks.

Fold the whites into the almond mixture, then fold in the apricot jam. Mix the dough until it comes together in a smooth ball.

Pinch off pieces of dough about 4 cm (1 1/4-inch) in diameter and roll each into ovals.

In a small bowl, lightly beat the egg white with a fork to break it up. Put the sliced almonds on a plate. Working with 3 or 4 at a time, roll each piece of rolled cookie dough in the egg white and then roll it in the almonds, to coat generously. You may need to press them on with your hands.

Place the cookies on the baking sheets, evenly spaced apart. Bake for 25 - 30 minutes or until golden brown all over.