Whisk together dry ingredients in a medium bowl. Add in egg, milk, buttermilk, and melted butter and whisk. Batter should be thick, but very pourable. Feel free to add a little more milk to adjust.
Use a 1/3 cup measuring cup to pour batter onto a pre-heated griddle or skillet over medium heat. Lightly oil/butter the skillet before cooking.
Cook pancakes until they start to bubble a bit on the surface, about 3-4 minutes. Then flip and cook for another 1-2 minutes.
Serve pancakes while warm with extra butter and maple syrup.