Step 1

Arrange a rack in the middle of the oven and heat the oven to 350°F. Butter the bottom and sides of a 10-inch cast iron skillet. Place the skillet in the oven to heat while you make the batter. Melt remaining 2 tablespoons butter, set aside to cool.

Step 2

Place 2 cups whole milk, 1/2 cup granulated sugar, 2 large eggs, 1 1/2 tablespoons white vinegar, and the melted butter in a large bowl. Whisk to blend well. Add 1 cup all-purpose flour, 3/4 cup yellow cornmeal, 1 teaspoon baking powder, 1/2 teaspoon baking soda, and 3/4 teaspoon fine sea salt. Whisk until nearly smooth. The batter will very thin. Set it aside to rest for about 5 minutes.

Step 3

Remove the hot skillet from the oven. Pour in the batter. Pour 1 cup heavy cream directly into the center. Bake until the cake is deeply golden and beginning to pull away from the sides of the pan — the cake will still jiggle a bit on top and might have a few cracks along the surface — 50 to 60 minutes. Let cool slightly before slicing into wedges, or spoon warm from the pan. Either way, serve with a drizzle of maple syrup.