Preheat oven to 350°F and butter an 8x8-inch (2-quart) casserole dish with 2 tablespoons of butter.
5 tablespoons unsalted butter
In a medium, heavy-bottomed saucepan set over medium heat, bring the milk and buttermilk to a very low simmer (stirring constantly) just until small bubbles begin forming around the edges of the saucepan.
1½ cups whole milk, 1½ cups buttermilk
Slowly pour the cornmeal into the milk/buttermilk, whisking continuously. Remember to scrape the sides of the pan as you whisk. Cook, whisking or stirring constantly, until cornmeal dissolves and the mixture thickens, about 7-9 minutes. Take the cornmeal off the heat and stir in the remaining 3 tablespoons of butter and all of the salt and honey. Stir until the butter melts, and let the mixture rest for 10 minutes.
1 cup finely ground white cornmeal, 1¼ teaspoons kosher salt, 1 tablespoon honey
Place the egg yolks in a medium bowl and whisk lightly. Add 2 cups of the cooled cornmeal and whisk until incorporated. Pour the egg yolk/cornmeal mixture back into the remaining cornmeal (in the saucepan) and whisk until combined.
3 large eggs
In a clean bowl of a stand mixer fitted with the whisk attachment, beat the egg whites on medium-high speed, with the whisk attachment, until stiff peaks form. Gently fold the egg whites into the cornmeal mixture until no streaks remain and the batter is smooth. Do not over-mix.
Carefully transfer the batter into the prepared dish and sprinkle with Turbinado or Raw sugar, if desired. Bake at 350°F for 35-40 minutes, or until the bread is puffed, firm, and light golden brown. Transfer the bread to a cooling rack and let it sit for about 5 minutes. It will deflate within a few minutes after removing from the oven.
Turbinado or Raw sugar
Serve warm (or hot) and with a drizzle of honey (if desired).