Combine blueberries, lemon juice and 1 tbsp of the sugar in a saucepan over medium heat. Cook 5 to 7 minutes or until berries burst and become a bit syrupy. Cool.
In a bowl, whisk egg yolks and 1/4 cup of the sugar. Heat milk, cream, salt and remaining 1/4 cup sugar in a pot until barely simmering. Remove from heat and slowly whisk into yolk-sugar mixture to temper. Pour back into pot and cook over medium heat. Stir constantly until mixture coats the back of a wooden spoon (170° to 180°), 4 to 8 minutes. Pour through strainer into a new bowl; cool over an ice bath or in refrigerator.
Whisk vanilla and blueberries into cooled liquid. Process in an ice cream maker according to manufacturer’s directions. Add pistachios during last 5 minutes. Transfer to a lidded container and freeze at least 2 hours.