Preheat the oven to 400°F.
2. Spoon a bit (a tablespoon or so) of the melted butter into the bottom of a 9-inch pie plate, cake pan, or cast-iron skillet (any 1-quart/1-liter baking dish). Using a brush or your fingers (I am using my fingers), grease the dish all along the bottom and up the sides.
3. In a medium bowl, whisk together the flour, cornmeal, brown sugar, baking powder, salt, and pepper (if using).
4. In another medium bowl or measuring cup, whisk together the eggs, mayonnaise, and buttermilk.
5. Whisk the wet ingredients into the dry ingredients, but just until combined (a few dry spots/lumps are okay). Add the remaining melted butter to the batter and gently fold until it’s totally incorporated.
6. Pour the batter into the prepared pan, smooth the top, and bake until the edges are deeply browned and crispy and the top is a lovely, sunflower-y golden yellow color (if it cracks, I’m into that), 20–25 minutes.
7. Remove from oven and let cool a few minutes before slicing into. While you wait, if you like, mix some softened butter with a good amount of honey and a healthy pinch of flaky salt. Mix until shiny, glossy, and spreadable and serve with the cornbread