Add all the ingredients to a mixing bowl and blend using a hand mixer or immersion blender until smooth.
1 cup (125g) flour, 3 large eggs, 3/4 cup (180ml) milk, 1/2 cup (120ml) sparkling water, 2 tablespoons sugar, 2 tablespoons melted and cooled butter, 1 teaspoon vanilla extract, a pinch of salt