Here is my favorite recipe for cardamom ice cream. This recipe is adapted from Jill Norman's "Herbs & Spices: The Cook's Reference.
2 cups 2% milk or light cream
1 vanilla bean, split lengthwise
6-8 whole green cardamom pods, lightly crushed or cardamom seeds
1/2 to 3/4 cup sugar (use less sugar if you don't enjoy sweet ice cream)
4 egg yolks
3/4 cup whipping cream
1/8 teaspoon ground cardamom
1/8 teaspoon rose or orange blossom water (optional)
Put the milk, or light cream, vanilla bean and crushed cardamom pods into a heavy pan and bring slowly to a boil. Remove from heat, cover, and let infuse for 20 minutes. Take out the vanilla bean and scape the seeds into the liquid. Remove the crushed green cardamom pods.
Beat the egg yolks and sugar until thick and pale. Gently reheat the milk or cream and beat a little of it into the egg yolks. Pour the egg mixture into the cream and return the pan to a low heat. Stir until the custard is thick enough to coat the back of a spoon; it will take several minutes. Do not let it boil, or you'll get pieces of scrambled egg.
Remove the pan from the heat and continue to stir until it has almost cooled. Whip the whipping cream lightly and fold it into the custard. Add the 1/8 teaspoon of ground cardamom and rose water (if using). Freeze in an ice cream maker following the manufacturer's instructions.
Be careful not to add too much cardamom to the recipe. Cardamom is a very strong flavor, and too much of it can cause a soapy taste.
Serve with toasted pistachios or toasted coconut.
If you are short on time then you can purchase a good quality vanilla ice cream. Allow to soften then fold in 1 teaspoon ground cardamom, pistachios/coconut. Return to freezer for 5-10 minutes. Then serve and enjoy :)