1Heat electric skillet, griddle, or frying pan over low heat while preparing ingredients.
2Mix flour, sugar, salt (if using salted butter eliminate salt), baking powder, and baking soda in medium bowl ~ I use my Kitchen Aide Mixer so I add all these ingredients into my 4.5qt mixer bowl.
3Microwave buttermilk and milk in a 2-cup Pyrex glass measuring cup to room temperature ~ 20 to 30 seconds.
4Whisk in egg, melted butter, and vanilla extract into the 2-cup Pyrex glass measuring cup (after microwaving to room temperature)
5Add wet ingredients into dry ingredients and mix for 30 seconds or until just mixed ~ if not using an electric mixer, whisk by hand for 30 seconds or until just mixed.
6Let batter sit for about 15 minutes.
7Increase heat to medium (if using electric skillet heat to 375 degrees) and spray surface with cooking spray
8Pour batter about 1/4 cup at a time. Work in batches, if necessary, avoid crowding.
9When pancake bottoms are golden brown and tops start to bubble, 2 to 3 minutes, flip pancakes; cook until golden brown on remaining side. Repeat, using cooking spray on electric skillet, griddle, or frying pan for new batch.