In a small bowl, mix the flour, sugar, baking powder, baking soda, and salt. Mix well to combine. Set that aside.
In another bowl, add the vanilla kefir, vanilla extract, egg, and melted butter to a large bowl and mix again.
Pour the dry ingredients into the wet ingredients and mix until just combined. It's ok if there are a few lumps left in the batter. You want the batter to be thick.
Preheat a large skillet or a griddle over medium-high heat. Add a tablespoon of butter to the hot pan. Use a non-stick pan if you can which will prevent the pancakes from sticking.
Spoon the batter into the hot griddle or hot skillet. Let the batter cook for a couple of minutes. When the edges start to dry out and there are small bubbles in the center of the pancake, flip the pancake.
Cook the second side for 2-3 minutes. Continue with the rest of the batter until all the pancakes are made. Serve immediately.