Japanese Sweet Potato

by

Flash in the Pan

In Okinawa, the Tokko shrine honors a sailor named Maeda Riemon for bringing sweet potatoes to Japan in 1705. He’d encountered this plant, which isn’t actually a potato, in the Ryukyu islands of the South China Sea, where locals called it “Chinese potato.” Riemon was so impressed by the flavor that he brought tubers home for his garden.  Before long, Riemon’s neighbors began growing sweet potato, and it spread vigorously throughout Japan. It produces huge yields, and the crop is easy to stockpile and store. In those days, crop failures and famines were common, and the Satsuma-imo, as it was called, fed millions through harsh times, including World War II, saving many thousands from starvation.

“Satsuma-imo” means baked Satsuma potato. Its name includes cooking instructions because baked is the best way to cook it. The flesh becomes soft, fluffy and moist, with a vanilla-esque aroma and honey like sweetness. While the inside tastes like crème brulee, the chewy skin is mild and fun to eat as well. Altogether, baked Satsuma is a complete, stand-alone dish that doesn’t require a single condiment, side dish or even dessert.

Sweet potato comes from South America, and arrived the Ryukyo islands by way of China, where it had taken hold about a century earlier. Here in the US., Satsuama-imo grows in every state in the lower 48, but in the northern climes you will want to start it inside, in in a bucket of soil. By the time it’s warm enough outside for some sweet potato transplants, yours will be ready for the ground. You can plant Japanese Sweet Potatoes amongst other garden crops like tomatoes or spinach. They grow slowly, passing the time as ground cover between the other plants before eventually setting their own delicious subterranean crop.

While a baked Satsuma needs no improvement or modification, I decided to doctor one anyway. Since a baked Satsuma tastes so perfect, my plan was to prepare it in a way to that makes it taste even more like itself. Redundancy in the kitchen is a good thing, because doubling up can create more nuanced flavors. In this case, combining the pudding-like sweet potato flesh with the ingredients for custard improved the flavor while increasing the amount of final product. We have better pudding, and we have more pudding, thanks to the addition of flavors and textures similar to what a Satsuma already brings to the table. Baked slowly in the oven, the pudding develops a chewy shell, while staying soft in the middle. It tastes like eggnog, but thicker, with maple syrup for added sweetness, vanilla to match that syrupy Satsuma flavor, coconut milk for creaminess, and tapioca pearls, for fun.

Baked Satsuma

This recipe is the only instruction you need for Japanese Sweet Potato. It is also step one in my baked pudding recipe.

One spud serves one person

Turn on the oven to 350.

Using a fork, poke a few holes into the skin of each sweet potato.

Wrap them in foil if you wish. They will stay more moist that way, and more rosy perfumy, but without the dense gravitas of a naked baked potato.

Try with and without foil to see which you prefer.

Bake for about 2 hours, until totally soft all the way through.

Baked Satsuma Pudding 

Here we make pudding from a pudding-like tuber, along with more traditional pudding ingredients, to make a crème brulee, minus the torched sugar on top.  I’ve included optional instructions for adding tapioca pearls, if desired. Use 4-inch ramekins, ideally, of some kind of small, bakeable ware.

Makes two servings per pound Japanese Sweet Potato

  • 2 tablespoons tapioca pearls
  • 1 cup of milk
  • 1 pound of cooked Japanese Sweet Potato flesh (no skin)
  • 2 tablespoons tapioca flour
  • ½ cup coconut milk
  • 1 tablespoon cooking oil
  • ¼ teaspoon grated nutmeg
  • 1 tablespoon maple syrup or sugar
  • 1 teaspoon vanilla extract
  • ¼ teaspoon salt
  • 2 egg, beaten
  • Butter for greasing the ramekins

Preheat oven to 250.

Heat the tapioca pearls in the milk on low for about 20 minutes, or until soft, stirring enough to keep everything loose. When soft, let them cool.

Add the rest of the ingredients to a blender or food processor, and process until smooth. Add the egg and beat again until smooth. Stir in the milk-fed tapioca pearls, if using. Pour the mixture into two buttered ramekins, which should bring it to about ¾ full.

Bake for about 90 minutes, until stiff in the middle. Serve warm or cold.