½ cup (113 grams) unsalted butter2 tablespoons (28 grams) vegetable oil1½ cups (170 grams) stone-ground yellow cornmeal¾ cup (94 grams) all-purpose flour1½ teaspoons (4.5 grams) kosher salt½ teaspoon (2.5 grams) baking soda¼ teaspoon (1.25 grams) baking powder1½ cups (360 grams) whole buttermilk, room temperature1 large egg (50 grams), room temperature1 large egg yolk (19 grams), room temperature1 tablespoon (21 grams) clover honey, plus more to serve¾ cup (107 grams) honey-roasted peanuts, roughly chopped and divided½ cup (57 grams) ¼-inch-chopped seeded jalapeño
Preheat oven to 400°F (200°C).
In a light-colored 9-inch metal skillet (see Note), melt butter over medium heat. Cook until butter solids are amber colored and nutty in aroma, 7 to 12 minutes. Pour browned butter into a medium heatproof bowl; let cool for 10 minutes.
In a 9-inch cast-iron skillet, place oil; place skillet in oven until hot, about 8 minutes.
In a large bowl, whisk together cornmeal, flour, salt, baking soda, and baking powder.
In another medium bowl, whisk together buttermilk, 3 tablespoons (37 grams) browned butter, egg, egg yolk, and honey. Whisk buttermilk mixture into cornmeal mixture until combined. Fold in two-thirds of peanuts and jalapeño.
Remove hot skillet from oven; carefully pour batter over hot oil in skillet, spreading into an even layer with a small offset spatula. Sprinkle with remaining peanuts.
Bake until golden brown and a wooden pick inserted in center comes out clean, 18 to 22 minutes, loosely covering with foil to prevent excess browning, if necessary. Let cool in skillet for 15 minutes. Serve warm with honey and remaining browned butter.