Step 1

Combine coffee and Tia Maria in a bowl. Dip biscuits, 1 at a time, into the coffee mixture and use to line the sides of four 375ml (1 1/2-cup) capacity serving glasses. Drizzle with remaining coffee mixture.

Step 2

Use an electric beater to beat together the egg yolks and sugar in a medium bowl until thick and creamy. Add the mascarpone and beat until combined.

Step 3

Use a clean electric beater to whisk the egg whites in a bowl until soft peaks form. Use a metal spoon to fold half the egg white into the mascarpone mixture. Fold in the remaining egg white until combined. Spoon mascarpone mixture among glasses. Cover with plastic wrap. Place in the fridge for 6 hours to chill.

Step 4

Sprinkle with chocolate to serve.