In a large bowl, whisk eggs, sugar, salt, oat flour and tapioca flour.
Add vanilla extract and melted butter, mix in.
Cover with the plastic film and refrigerate for 1 hour or up to 1 day. Stir for a few seconds before using.
Heat a small pan and add the butter to coat. Pour the batter into the pan and spread it evenly. Cook until edges start to turn golden. Turn and cook other side until done. Transfer to the plate.
Enjoy with your favorite fillings!