Freeze ice cream freezer bowl overnight or according to your maker's directions.
Cook Black Raspberries (1 pint) and Granulated Sugar (1/4 cup) over medium to low heat for 6-8 minutes. Stir frequently and smash fruit with your utensil to help extract the juice.
Strain raspberry mixture through a fine sieve to remove seeds. Press berries against the sieve walls to fully extract the juice. It will yield about 1/2 cup of filtered juice.
In a medium saucepan, cook Whole Milk (1 3/4 cup) and Heavy Cream (1 1/4 cup) at medium heat until it comes to a boil, stirring frequently for about 8-10 minutes. Remove from heat.
In a large mixing bowl, whisk together the Egg (6), Granulated Sugar (1/2 cup), Vanilla Extract (1 teaspoon), and Salt (1/4 teaspoon). Stir in raspberry juice as well.
Temper the milk by very slowly incorporating the milk mixture into the egg mixture. Stir as you incorporate the milk.
Pour mixture back into your saucepan and cook at medium-low heat for an additional 10 minutes, stirring continuously. If the mixture starts to boil, reduce heat. Once cooked, remove from heat.
Filter mixture through a fine sieve to remove any impurities left from cooking.
Chill mixture completely by either placing the bowl in an ice bath for at least 30 minutes, or refrigerating for several hours. The mixture should be refrigerator-like temperature before placing in your ice cream freezer, or it won't freeze well.
Once chilled, transfer the contents into your ice cream mixer bowl and mix for 20 minutes.
Transfer the mix into a quart-sized container and freeze for at least 3 hours, or up to a few days, before serving for the best texture. Enjoy!