I finally succeeded at making some Japanese red beans ice cream that received approvals from my mum, my sisters and and my sister-in-law. The last attempt was a failure as I reduced the amount of sugar required, resulting in a bland and tasteless ice cream. Thanks to my mum's constructive comments, I did another experiment and finally got the right blend :) Here's the recipe!
For the azuki paste
1 cup washed azuki beans
1/3 cup sugar
3 cups water
A pinch of salt
For the ice cream
1 1/2 cups milk
1 cup whipping cream
3/4 cup sugar (or 1 cup if you prefer to have it a little sweeter)
4 egg yolks
1 teaspoon vanilla essence
For the azuki paste: Put beans in a saucepan full of water, bring to a boil, then drain in a colander. Return beans to pan, add 4 cups of water, cover and simmer until beans after very soft and have absorbed all the water. Stir in sugar and cook over low heat until sugar has dissolved and beans form a soft, chunky paste. Add salt and allow to cool. (I used the slow cooker for this which save me the trouble of watching over the stove. Simmering time maybe between 2.5-3 hours long, depending on the beans. Also with the slow cooker you can put everything in at once).
For the ice cream: In a saucepan, combine the milk and cream and bring to a simmer. While waiting, you can beat the egg yolks and sugar in a medium bowl. When the milk come to a boil, turn off the heat and pour about 1/4 cup of the liquid into the bowl with the egg yolk and whisk until smooth. Pour the yolk mixture back into the pan with the rest of the milk and cook over low heat until thick enough to coat the back of a spoon (custard like consistency). Stir in vanilla essence. Do not overcook or you may get lumps. Pour it through a strainer if required. Refrigerate until ready to use, preferably overnight.
The original recipe calls for adding the bean paste to the ice cream just 10 minutes before it freezes but I prefer to stir the beans (cooled) into the custard before I refrigerate it overnight. The amount of paste to stir into the custard is according to your preference - I used only half the amount prepared. Freeze the mixture in an ice cream maker according to the manufacturer's instructions.