For the syrup: In a medium saucepan, bring the Prosecco, sugar, lemon juice, lemon zest, star anise, and cinnamon stick to a boil, stirring occasionally, over medium-high heat, until the sugar has dissolved. Reduce the heat and simmer for 35 minutes until the mixture has reduced by half. Add the mangoes and raspberries to the syrup and allow the mixture to cool for 1 1/2 hours. Using a slotted spoon, remove the fruit and spoon into serving bowls. Discard the cinnamon stick and star anise. Pour the syrup into a pitcher. Refrigerate the fruit and syrup until ready to serve.;
Whipped cream: For the cream: In a medium bowl, using an electric hand mixer, beat the cream at high speed until thick. Add the sugar and continue to beat until the cream holds stiff peaks. Add the lemon zest and mix until just combined.
To serve: Put a dollop of cream on top of the fruit and drizzle each dish with the Prosecco syrup.