Preheat your oven to 160°C (320°F). Line a 20 x 20 cm (or similar rectangular) cake pan with parchment, making sure the sides are well covered so the batter can climb the walls as it bakes.
In a small saucepan, combine the Honey, Mizuame and Water and warm gently until the honey and mizuame are dissolved; do not boil. Remove from heat and let cool until just warm to the touch.
In a large mixing bowl, add the Egg and the Granulated Sugar. Using an electric mixer, beat on medium-high until the mixture is very pale, thick and ribbons fall from the whisk (about 10–15 minutes).
With the mixer running on low, slowly stream the warm honey syrup into the egg-sugar mixture until fully incorporated. Continue to mix briefly so the mixture is smooth and glossy.
Sift the Bread Flour over the whipped egg mixture and gently fold it in with a spatula in 2–3 additions. Fold just until no streaks of flour remain—overmixing will deflate the batter.
Pour the batter into the prepared pan, smoothing the top. Give the pan a couple of firm taps on the counter to release large air bubbles. If you like a bit of sparkle and crunch on top, sprinkle the surface with Zarame Sugar.
Bake in the preheated oven for 50–60 minutes, or until the top is golden, springs back when touched lightly, and a skewer inserted into the center comes out clean. If the top browns too quickly, tent loosely with foil for the remainder of the bake.
Remove the cake from the oven and let it cool in the pan for about 10 minutes. Then lift the cake out using the parchment and let it cool completely on a wire rack. For the best texture and flavor, wrap the cake and rest it for several hours or overnight before slicing into thin pieces.
