
Preheat your oven to 425°F. Place a cast iron skillet (10 or 12") inside to heat while you prep the batter.
In a small bowl, mix the plant milk and apple cider vinegar. Let sit for 5 minutes to create vegan buttermilk.
In a large bowl, mix together the cornmeal, flour, baking powder, baking soda, sugar, and salt.
Pour in the vegan buttermilk and oil. Stir until just combined—don’t overmix.
Carefully remove the hot skillet, melt the vegan butter in it, and swirl to coat.
Pour the batter into the sizzling hot skillet (you should hear it sizzle) and return it to the oven.
Bake for 20–23 minutes, or until golden and set in the center.
Let cool 10 minutes before slicing.