Anko(餡子) is a japanese name for red bean paste made from adzuki beans. There are also other names, An, Ogura, in Korea its called Pat, and in the origin country China it is called Dousha or Dourong. If it is made from white beans its called Shiroan, from chestnuts its called Kurian. The paste is used in a variety of cakes, desserts and sweets.

There are several ways to prepare Anko in Japanese cuisine, Tsubu-An means boiled red beans that were thickened with sugar, Tsubushi-An indicates the beans were mashed after thickening. In Japanese confectionary Koshi-An is used commonly, the beans are pureed after boiling, sifted to remove the skin and then thickened. For a quick preparation there is Sarashian, an instant powder from red beans.

In this instructable I will show you how to make Tsubu-An (also called Amani) because then the red beans have an improved preservation and you can make the refined versions later whenever there is demand.

Step 1: What You Need:

300grams adzuki beans
250grams sugar
water
baking soda (optional)

Equipment:

cooking pot
lid that fits inside of the cooking pot
colander
dishcloth
parchment paper

Step 2: Bad Ones Go Into Your Crop

The cooking procedure is supposed to maximise the water content inside of the beans. Up to 64% of the beans can be carbohydrates which are mostly starch. The starch consists of amylopectin and amylose in a ratio of 2 to 1. When cooking pasta, the heating process hydrates the amylopectin and lengthens the sugar chains. When cooking adzuki beans, free floating amylopectin could connect to other amylopectin molecules, close the chain and thereby prevent the lengthening and the access for our digestive enzymes. For our taste buds as well and although with a high sugar content, the beans then taste like pasta cooked without salt. This is why at first you have to sort out all the broken beans. They could spill starch through their openings into the cooking water. To obtain the best results you have to lengthen the amylopectin inside of sealed beans in a gentle cooking process.

Step 3: Soak the Beans

Wash the beans to remove dust and then place them in a container. Cover the beans with water and soak them for 12 hours or overnight. The beans will double in size and enable a consistent increase during the cooking. To soften the skins you can add a teaspoon of baking soda.

Step 4: Experiment

There are many recipes available for Anko and the soaking process can be found in 3 different ways. Either just water, or boiling water, or water with baking soda. So I made an experiment and tried all processes with just 5 grams of adzuki beans. After 12 hours the results were divided. In the cold water all beans stood upright and the water was cruddy. In the boiling water the water was less muddy but fizzy. The water with baking soda was not fizzy, not muddy, the beans were in disorder and had the highest increase in size. After I emptied the glass jars out there was dirt in the first 2 jars but not in the last one. But the beans in the third jar had the biggest increase in size. Clean or big, I can't decide which option is the better one.

Step 5: Sort Out Again

After soaking overnight pour the water away and sort out broken beans. You can see how uneven they swell in the secound picture. This would reduce the quality of the Anko.

Step 6: Start Cooking

Put the beans into a big cooking pot and cover them barely with water. Not too much water, don't put pressure on them. Catch broken beans with your cooking spoon and throw them away. But don't stir the ones in the cooking pot until sugar is added.

Bring the beans to a boil.

Measure 300ml of cold water and add half of it.

Step 7:

The beans must not be above the water or the skins could burst. With the heat they will soak the water very fast.

Add the secound half of the cold water when the water boils again and lower the heat to medium for about 45 minutes.

Step 8: Shibu-Kiri

Drain the beans in a colander and put them immediately back into the cooking pot with cold water. For very refined Shiro-An this is repeated several times. Wait 5 minutes then turn on the hob to let the beans simmer for 60 minutes.

Step 9: Otoshibuta

Prepare the parchment paper by placing the lid on it and cut it out with a scissor. Put both on top of the beans to prevent their movement in the hot water.

Step 10:

Place the dishcloth inside of the colander.

Step 11: Nama-An

After 60 minutes of simmering, pour the cooking pot into the colander. Then press the dishcloth gently to remove excess water and put half of the beans back into the cooking pot.

Step 12: Add Sugar

After draining the water you can add sugar. It should be a bit less than the weight in beans, around 50grams. For the 300grams in beans we need 250grams sugar.

Step 13: Stir the Sugar In

Now you can stir the beans with the sugar. The dissolving sugar binds some of the water and suddenly your beans swim again. Add the secound half of the beans and you can either simmer the mixture on very low heat for 2 hours or stir it on high heat until you can see the bottom of the pot after a stroke.

Step 14: Ready

The Tsubu-An is now ready, take it out of the pot and place it on a clean surface like a baking tray and let it all cool down.

Step 15: Freezing

The procedure takes a lot of time, it makes sense to prepare more Anko than you need and freeze the rest. Put it into a freezer bag and take a chopstick to separate the Anko into portions as shown in the pictures. It is said to stay fresh in the freezer for up to 6 weeks.

If you need the refined versions for a dessert just mash the beans and sift them to get rid of the skins.

Step 16: Simple Mochi

I will release some recipes within the next weeks to make use of the fresh made Anko, like Doryaki and Yokan. Meanwhile you can just add it to any dessert or make a very simple mochi with glutinous rice flour. In contrast to its name it does not contain gluten, it is just very gluey. Mix 50 grams rice flour with 50 grams water and a spoon of sugar. Add the water by the spoonfull and stir the mixture. Then put it into a microwave at 500W for 1 minute. Take it out, stir with a spoon and again for 1 minute at 500W. Then spread out potato starch on a silicon kneading mat and put the microwaved mochi on it. Spread some starch on top and fold the mochi, but be carefull it is very hot inside! Let it rest to cool down a bit, then roll it out, hammer or beat it flat and cut out circles.

Step 17:

Brush off the starch, place some Anko inside and fold the mochi. I have a jambú plant in my garden and used the petals for an edible and spicy decoration for the tasty dessert. Try it out!