In a medium saucepan, over medium heat, combine the heavy cream, half-and-half, kosher salt, and sugar. Cook until sugar is dissolved. Do not let it boil. Remove from heat.
In a food processor blend the blueberries, extracts, and cardamom.
Place the egg yolks in a medium bowl, and whisk well with a fork.
Using a 1/3 measuring cup, add some of the hot cream mixture to the egg yolks, and whisk while you combine. Add another 1/3 cup - mix. Then a final 1/3 cup - mix. Whisk the egg mixture into the rest of the cream, and return the pan to the stove.
Cook on medium-low heat for 5 minutes, stirring often. Remove from heat, and pour the mixture into a heatproof bowl fitted with a sieve/fine mesh strainer. Add the blueberries and stir to combine.
Transfer to the fridge for 4-12 hours (preferably) or until completely cooled.
Add the ice cream base to your ice cream maker of choice, churning until it has reached your preferred level of "doneness".
Transfer to an air-tighter container, pressing a piece of plastic wrap over the top of the ice cream, ensuring it makes contact with the ice cream.
Half-and-half seems to be an American product. It is half whole milk and half cream. If you can't find it at your store, sub in 1/2 cup of whole milk and 1/2 cup of heavy cream.
Homemade Blueberry Ice Cream
Amount Per Serving (12 cup)
Calories 288Calories from Fat 189
% Daily Value*
Saturated Fat 12g75%
Vitamin A 925IU19%
Vitamin C 6mg7%
* Percent Daily Values are based on a 2000 calorie diet.