In a large bowl, mix sourdough starter, flour, sugar, milk and vinegar together.
Set aside, covered loosely with plastic wrap
Preheat waffle iron
In a small bowl, mix beat egg, butter and vanilla together
Pour mixture into large bowl of starter batter, and mix well
Sprinkle baking soda and baking powder over batter and mix well
Add batter to waffle iron – I use a ladle that holds approx. 1/3 cup. One ladle scoop for ½ the waffle ironplate. Close lid and set a timer for 5minutes and 30 seconds. (That’s what I use, and find it’s perfect for my waffle iron – adjust time or waffle iron temp to suit your own preferences)