My wife likes to use buttermilk for many dishes. She even likes to drink it (especially the high-octane kind from Harrisburg farms in Pennsylvania). We have never seen buttermilk in Japan. Originally buttermilk was leftover from churning butter out of cream and as a result had some small chunks of butter floating in it. This type is known as traditional buttermilk. The buttermilk used today is known as cultured buttermilk and is produced from cows milk fermented using one of two species of bacteria; Lactococcus lactis or Lactobacilliu bulgaricus. The fermentation creates lactic acid which is what gives buttermilk its characteristic tart taste. The fermentation also means it lasts a long time. (My wife found, for example, that buttermilk marked with a due date of Jan 30 was perfectly good in April of the same year). In any case, one day, she decided to make this buttermilk pudding.
I myself would never like to "drink" buttermilk by itself, even though I have tasted it, but using in baking or this type of dish it is quite good.
2 tsp. powdered gelatin
2 tbs. water
1/2 cup half and half plus 1/2 cup milk (or you could use 1 cup of heavy cream instead for a really luxurious pudding).
1/2 cup sugar
1 tsp. vanilla
2 cups buttermilk
Bloom the gelatin in the water. Put the half & half, milk and sugar in a sauce pan and heat until the sugar is dissolved. Remove from heat and add the gelatin stirring until it is dissolved. When the milk mixture has cooled to room temperature add the vanilla and the buttermilk. Mix thoroughly. Pour into small ramekins or Pyrex dessert bowls. Put into the refrigerator until set.
This is a lovely pudding. It is not too sour or too sweet. It has a nice fresh tangy taste and smooth texture. It is also fairly easy to make.