Heat cast iron (or heavy bottom) skillet to medium.

In mixing bowl, whisk together flour, baking powder, baking soda, sugar and salt; set aside.

In a medium size mixing bowl, lightly whisk together the buttermilk, melted butter, egg and vanilla. Note: Be sure the melted butter has cooled before adding to the mixture.

Add the flour mixture to the wet mixture and whisk or stir until combined. If mixture seems to dry, add more buttermilk (or whole milk) until mixture is almost pourable. It should still have a thick consistency and be lumpy. Let sit for at least 5 minutes before making pancakes.

Heat cast iron pan (or heavy bottom pan) to medium. When the pancake batter is ready, coat the bottom of the pan with half the vegetable oil and half the butter.

With a ladle or large spoon, drop about 1/4 cup of the batter onto the center of the pan. Smooth out the batter to create a round pancake. It should be about 3/4 inch thick.

When bubbles in the center of the pancake pop, flip the pancake. It's ok to lift the underside of the pancake with a spatula to peek to see if it's golden brown. Once flipped, cook another minute, or until the other side is golden brown. Continue with remaining batter, adding more oil/butter to pan as needed to keep pancakes from sticking.