300g fat-free natural Greek-style yogurt
3 level tbsp sweetener granules
400g blackcurrant
Juice of 1 lemon
1 Whisk the yogurt, 1 level tbsp sweetener and 1 tbsp cold water together in a bowl.
2 Put the blackcurrants, lemon juice, 3 tbsp cold water and the remaining sweetener in a food processor and blend to a smooth purée. Rub through a sieve into a measuring jug and make up to 375ml with cold water.
3 Pour a layer of the blackcurrant purée into 5 x 75ml ice-lolly moulds and a layer of the sweetened yogurt into another 5 x 75ml ice-lolly moulds. Freeze for 30-45 minutes, or until just firm. Add a layer of sweetened yogurt to the moulds containing the blackcurrant purée and vice versa, then freeze until just firm. Finish with another layer of the mixture you used first for each mould, so you have an alternating pattern.
4 Freeze the lollies for a further 30-45 minutes, then insert the lolly sticks, pushing them about halfway into the mixture. Freeze for 8 hours, or until solid.
5 To serve, dip the moulds very briefly in hot water and slide out the lollies.