I make Teaberry Ice Cream (It’s a PA thing). I don’t use heavy cream and instead use 4 cups half and half. Teaberry oil can be found online (don’t use much of any mint oil as it is usually VERY strong - 1/2 teaspoon usually does it). Any flavoring can be used - just add it at the end when you put the custard in the machine. Very good with good vanilla beans!
1 cup heavy cream
3 cups half-and-half cream
8 egg yolks
1 cup white sugar
1/8 teaspoon salt
Pour the heavy cream and half-and-half cream into a heavy saucepan, place over medium-low heat, and heat until barely simmering, stirring frequently. Turn the heat down to low.
Whisk together the egg yolks, sugar, and salt in a large bowl until thoroughly combined.
Slowly pour about 1/2 cup of hot cream mixture into the egg yolk mixture, whisking constantly. Repeat three times more, whisking thoroughly before adding each additional 1/2 cup of hot cream to the egg yolk mixture. Pour the egg yolk mixture back into the saucepan with the remaining hot cream, and whisk constantly over medium-low heat until the mixture thickens and will coat the back of a spoon, 5 to 8 minutes. Do not let mixture boil.
Pour the ice cream base into a bowl and allow to cool for about 20 minutes; place in refrigerator and chill overnight. The next day, pour into an ice cream maker, and freeze according to the manufacturer’s directions. Remove the ice cream, pack into a covered container, and freeze for 2 hours or overnight before serving.