Crack the egg into a bowl, add the honey, water, and mirin, and whisk together.

Add the rice flour and baking powder to the bowl and mix until combined.

Pour the batter into the pan, filling each mold about 80% full, then add sweet red bean paste on top. Spread the filling as evenly as possible.

Spoon more batter over the red bean paste, close the lid, and cook for about 3 minutes.

When done, use a bamboo skewer or similar tool to remove the taiyaki. Trim any excess with kitchen scissors if needed.

If you don't have a taiyaki pan, cook the batter like pancakes in a skillet and make dorayaki instead!

I used this rice flour.