Strain orange juice, combine with 90gm sugar and ¼ cup water in a saucepan, bring to the boil and cook for 5-7 minutes until a deep golden colour. Cool.
Combine cream, milk, orange rind and Grand Marnier in a heavy-based saucepan and bring almost to the boil. Combine egg yolks and remaining sugar in a bowl and whisk until thick and pale, then gradually whisk in hot milk mixture. Return mixture to saucepan and stir over low heat until mixture thickens enough to coat the back of a wooden spoon. Do not boil. Remove from heat and strain through a sieve into a bowl and cool. Pour into an ice-cream machine and freeze according to manufacturer’s instructions. When almost churned, add orange syrup and continue churning. Place ice-cream in freezer until required.
For almond praline, combine sugar and ½ cup water in a saucepan over medium heat and cook for 5-7 minutes until golden, add nuts, pour onto a lightly oiled tray and cool. Place praline in a plastic bag and, using a rolling pin, crush until almost fine. Place in an airtight container until required.
Using a small ice-cream scooper, scoop ice-cream into small balls and place on a chilled baking paper-lined tray. Freeze overnight, then insert a wooden cocktail fork or toothpick into the top of each ball and return to freezer for 3-4 hours or until firm.
Melt chocolate in a heat-proof bowl over a saucepan of gently simmering water. Remove from heat and cool slightly. Place a second baking-paper lined tray in freezer. Working quickly, dip ice-cream balls one at a time into cooled chocolate, shaking off excess, then scatter with crushed praline and add to tray in freezer. Freeze for 2-3 hours or until set hard. Serve immediately from freezer.