Blend the blueberries with lemon/lime zest & juice, and sugar until silky smooth.
Simmer the mixture over medium heat for 10–15 minutes.
Remove from heat and chill in the fridge for 1–2 hours. (Optional: strain through a sieve for smooth texture.)
Whip the cream to soft peaks and gently fold in the condensed milk.
Then fold in the cooled blueberry mixture and glucose syrup.
Pour into a freezer-safe container and freeze for at least 6 hours.
Let rest in room temperature for a moment before serving.
