- Set a bowl into an ice water mixture to keep it cold and ready for the ice cream mixture.
- Combine the mashed strawberries, salt, and 1/4 cup sugar in a saucepan. Mix thoroughly and let sit for 30 minutes. Mix once or twice as it sits to ensure sugar is dissolved.
- Meanwhile, whisk egg yolks and 1/4 cup sugar in a medium bowl until combined and pale yellow.
- Heat the milk, cream, 1/4 cup sugar in a saucepan over medium heat, stirring occasionally, until milk starts to steam.
- Gradually whisk into yolks until combined. Then add back milk mixture to the saucepan. Stirring frequently until it is steaming again.
- Once custard is ready, strain into the bowl set in the ice-water bath and stir occasionally until cool. Taking the saucepan with the strawberries, heat on medium and cook for 2-3 minutes and then strain the juice out.
- Put the strained berries into a bowl and add the lemon juice and rum. Allow to cool. Take the strawberry juice and allow to cool in another ice bath or in the refrigerator.
- Once cooled combine with custard and also add in vanilla. When custard has cooled enough, start the machine and churn according to manufacturer directions.
- As the mixture begins to firm up, add the strawberries last and allow to churn or mix in with a soft spatula and freeze to firm up.