In a saucepan, combine black raspberries and sugar. Simmer over medium heat for 10 minutes, stirring occasionally, until raspberries break down and release their juices.

Strain the raspberry mixture through a fine-mesh sieve into a bowl, pressing on the solids to extract as much juice as possible. Discard the solids.

In a separate bowl, whisk together heavy cream, whole milk, egg yolks, vanilla extract, and salt.

Slowly whisk the warm raspberry mixture into the cream mixture, a little at a time.

Pour the mixture into your ice cream maker and churn according to the manufacturer's instructions. This usually takes about 20-30 minutes.

Once churned, transfer the ice cream to an airtight container and freeze for at least 2-3 hours to allow it to harden further.