Measure the butter: set aside 1 tablespoon for the skillet and melt the remaining 7 tablespoons in a small heatproof bowl; let the melted butter cool slightly while you prepare other ingredients.

In a medium bowl, whisk together 1 cup plain Greek yogurt, 1/2 cup milk, 1/4 cup honey, and 2 large eggs until smooth and combined.

In a large bowl, whisk together 1 1/2 cups cornmeal, 1 cup all-purpose flour, 2 tablespoons granulated sugar, 2 1/2 teaspoons baking powder, 1/2 teaspoon baking soda, and 1 1/4 teaspoons kosher salt.

Pour the wet mixture into the dry ingredients and stir gently with a spatula or spoon just until mostly combined and only a few streaks of flour remain.

Pour the cooled melted butter (7 tablespoons) into the batter and fold gently until fully incorporated. Do not overmix.

Let the batter rest while you preheat the oven (resting improves texture). You may refrigerate the batter overnight here; if you do, let it come to room temperature before baking.

Place a 10-inch cast iron skillet on the center oven rack and preheat the oven to 425°F.

Very carefully remove the hot skillet from the oven. Reduce the oven temperature to 375°F. Use the reserved 1 tablespoon butter to coat the bottom and sides of the hot skillet (melt or spread the tablespoon if needed).

Pour the batter into the buttered skillet and smooth the top gently. Return the skillet to the center rack.

Bake at 375°F until the center is set and a toothpick inserted in the center comes out clean, about 22 to 25 minutes.

Let the cornbread cool in the skillet about 10 minutes, then slice and serve directly from the skillet. Serve with additional butter and honey if desired.