Combine the first 8 ingredients in a heavy large saucepan. Bring to a boil over medium-high heat, stirring until the sugar dissolves. Boil until the syrup is thick and the mixture is reduced to 2 cups, about 12 minutes. Discard the bay leaf; let the syrup cool.
Strain the syrup through a fine sieve into a medium bowl. Add the orange juice and lemon juice. Pour into a bowl, cover and refrigerate overnight.
Transfer to an ice cream maker and process according to the manufacturer's instructions. Transfer the sorbet to a container, cover, and freeze until firm, at least 6 hours and up to 3 days.
Notes
I use Trader Joe's fresh orange juice and it works just fine.
The sorbet will process better if the mixture is quite chilled before putting into your ice cream maker.