In a medium saucepan, combine the sugar and water over medium heat. Stir until the sugar is completely dissolved, creating a simple syrup. Remove from heat and let cool.
While the syrup cools, wash the raspberries and add them to a blender or food processor. Blend until smooth. You can strain the mixture through a fine mesh sieve to remove the seeds for an extra smooth texture, if desired.
In a large mixing bowl, combine the raspberry puree, freshly squeezed lemon juice, lemon zest, and cooled simple syrup. Add a pinch of salt to enhance the flavors. Mix well until all the ingredients are fully incorporated.
Pour the mixture into a shallow dish or a sorbet maker. If using a shallow dish, place it in the freezer. Stir the mixture every 30 minutes with a fork to break up the ice crystals, until the sorbet is firm and flaky (about 3-4 hours total). If using a sorbet maker, follow the manufacturer's instructions.
Once the sorbet is fully set, scoop it into bowls or cones, and serve immediately.
Notes
Garnish with fresh mint leaves or additional raspberries for a pop of color before serving.