How to prepare:
1. First, prepare your simple syrup. Combine sugar and water in a medium saucepan, bring to a boil over medium-high heat, then turn down heat to low and cook until sugar is completely dissolved. Set aside to cool.
Note: You can speed the cooling process by transferring the syrup into a bowl, then placing the bowl in an ice batch, stirring the syrup constantly until it cools.
2. Combine blueberries and lemon juice in a food processor or blender. Process until very smooth, then pour through a fine mesh sieve, pressing down on the solids with a silicone spatula to extract as much liquid as possible. Discard the leftover skins.
3. Stir together blueberry puree and simple syrup, then place in the fridge to chill for at least 8 hours.
4. When mixture is thoroughly chilled, it's time to churn the sorbet.
If using an ice cream maker: Churn your sorbet according to the manufacturer's directions, then transfer sorbet to a resealable container and place in the freezer for at least 2 hours before serving.
Without an ice cream maker: Pour sorbet mixture into a shallow pan and place in the freezer. After 30 minutes, remove and beat the mixture using electric beaters or a sturdy fork. (This is to break up the ice crystals that are forming and churn the mixture so that it freezes more evenly, yielding a smoother sorbet.) Place back in the freezer, and repeat this process every 30 minutes or so, until the sorbet is too hard to churn. Transfer to a resealable container and freeze until ready to serve.