Make the cornmeal soaker

Place the cornmeal in a medium bowl. Pour the boiling water over it and stir until evenly hydrated. Let it sit for about 30 minutes, or until warm rather than hot.

Warm the milk mixture

In a small saucepan over low heat, warm the butter, honey, and milk just until the butter is melted and the mixture is smooth. Remove from the heat and let cool to lukewarm.

Mix the dough

In the bowl of a stand mixer fitted with the dough hook, combine the cornmeal soaker, milk mixture, yeast, salt, spelt flour, and 300 grams of the all-purpose flour. Mix until a shaggy dough forms.

Continue mixing and add the remaining all-purpose flour in stages, about 50 grams at a time, mixing well after each addition. If the dough still feels too loose, add 1 to 2 tablespoons more flour, as needed. The dough should feel soft and workable, slightly tacky but not wet or stiff.

Knead on medium-low speed until the dough becomes smoother and more cohesive, about 5 to 7 minutes.

Proof

Place the dough in a lightly greased bowl, cover, and let it rise until doubled, about 1 hour, depending on the temperature of your kitchen.

Gently deflate the dough and turn it out onto a lightly floured surface. Shape into a loaf and place seam- side down in a greased or parchment-lined 9×5-inch loaf pan.

Cover and let the loaf rise until it crowns nicely above the rim of the pan.

Bake

Meanwhile, preheat the oven to 350°F (175°C).

Bake for 40 to 45 minutes, or until golden brown and the loaf sounds hollow when tapped on the bottom. If you check the internal temperature, it should register around 190 to 200°F in the center.

Remove the loaf from the pan and brush the top with melted butter while still warm. Let cool before slicing.