Preheat the oven to 375-degrees. Spray an 8x8-inch square pan and line with parchment. Spray the parchment.
Combine the flour, cornmeal, leavening, salt, and sugars in a large bowl. Whisk to combine.
In a large measuring cup, whisk together the buttermilk, melted butter, oil, egg and yolks, until incorporated.
Pour the liquid ingredients into the dry and using a rubber spatula, gently combine the two. The batter can be lumpy and perhaps there's even a streak of flour or cornmeal, that's okay.
Transfer the batter to the prepared pan and bake for 25 to 30 minutes, rotating the pan after 12 minutes. Begin checking for doneness at 20 minutes (I think the sweet spot is 28 minutes). A wooden skewer should come out clean.
While the bread bakes, warm the butter and honey in a small saucepan over medium heat until the butter melts. Once removed from the oven, brush the cornbread with the butter honey glaze and wait 15 minutes before serving. The cornbread will keep for at least a day or two on the counter, tightly wrapped — it gets moister and more flavorful on the second day (as do many quick breads, FYI). Yum.