Separate the egg whites and egg yolks into two separate bowls.

In a saucepan, combine the milk and butter. Heat over medium-low until the butter is fully melted.

In a large mixing bowl, add the cake flour. Gradually pour in the warm milk and butter mixture, stirring gently as you pour to combine evenly.

Add the egg yolks one at a time, mixing well after each addition until fully incorporated. (Check visual reference for desired consistency.)

Stir in the honey and vanilla extract, mixing until smooth.

In a clean bowl, beat the egg whites with a hand mixer. Once they become foamy, begin adding the sugar in three parts.

Continue beating until stiff peaks form and the meringue holds its shape.

Add two ladles of the beaten egg whites into the egg yolk mixture and gently fold to lighten the batter.

Then add the remaining meringue and carefully fold until the mixture is fully combined and smooth.

Transfer the batter into a parchment-lined baking pan. Tap the pan gently on the counter to release any large air bubbles.

Place the baking pan inside a larger tray and pour in enough hot water to come about three-quarters of the way up the sides of the cake pan.

Bake at 300°F (150°C) for 60 minutes using the water bath method.