Japanese Dorayaki (Pancakes with Sweet Red Bean Paste)

Soak aduki beans in cold water overnight. The next day, drain the water, place beans in a pot with fresh water, bring to a boil, then drain the first water. Add fresh water again and simmer on low heat for 60-90 minutes until beans are tender. Drain the water (reserve a little), then mash the beans with a fork or potato masher. Add sugar and a pinch of salt, then cook, stirring, for another 10-15 minutes on low heat until thickened and creamy. If too dry, add a little reserved cooking water. Let cool completely.

In a large bowl, whisk eggs with sugar, honey, and mirin until light and frothy. In a small bowl, dissolve baking soda in 2 tbsp water, then add to the egg mixture. Sift in the cake flour and gently mix until just combined. Do not overmix! Cover the bowl and let the batter rest at room temperature for at least 15-20 minutes.

Heat a non-stick pan over medium-low heat. Lightly oil it with a paper towel. Pour a ladleful of batter into the pan (about 2 tbsp per pancake) to form circles about 8-10 cm (3-4 inches) in diameter. Cook for 2-3 minutes until bubbles appear on the surface and the bottom is golden brown. Flip and cook for another 1-2 minutes on the other side. Transfer to a wire rack to cool and repeat with the remaining batter.

Once the pancakes and anko have cooled, take one pancake, spread a generous amount of sweet red bean paste on it, then cover with another pancake, gently pressing to distribute the filling evenly. Repeat with the remaining pancakes and anko. Serve immediately or store in an airtight container.