Preheat the oven to 180 °C and line a baking sheet with baking paper.
Combine muesli, sultanas and almonds in a large bowl. Sift flour over the muesli mixture. Make a well in the centre.
Combine butter, syrup and egg in a jug. Pour into well. Stir to combine. Using 2 tablespoons of muesli mixture at a time, shape into balls. Place balls on prepared trays and flatten slightly.
Bake for 20 minutes or until golden. Allow cooling on trays
Meanwhile, place the chocolate in a heatproof, microwave-safe bowl. Microwave on high (100%) for 1 minute or until just melted. Stir until smooth. Using a spoon, drizzle chocolate over the biscuits. Allow setting at room temperature. Serve.
Store for up to 1 week in an airtight container at room temperature.