Sourdough Pancakes - Testing

I adapted the Panekoeken recipe for sourdough, which made nice flapjacks with a satisfying chew. But then I didn't write anything down. So I'm starting again.

1 - This worked pretty well, but I only had 2 eggs, therefore I can't consider this a first attempt. With the missing egg, the mixture was too liquid and the edges thinned out to the point where it would damage the pancake when I tried to lift it. But it sure did bubble!

1 1/2 cup sourdough starter
1 1/2 cup white flour
1 cup milk

THEN
1 1/2 cups sourdough and milk mixture
2 tsps. sugar
1 tsp. baking soda
3 eggs
1 1/2 cups milk
A splash of vanilla (1 tsp. - 1 Tbsp., to taste)
1 Tbsp oil
Butter for frying.

1. The day before cooking, mix together the sourdough starter, flour and 1 cup of milk. Cover with a tea towel and leave in a warm place for about 24 hours.
2. THE NEXT DAY.
3. Take 1 1/2 cups of the sourdough and milk mixture and store the rest in the refrigerator for another time. Keeps for about a week.
4. Add sugar and baking soda, mixing these in.
5. Add the eggs and whisk thoroughly before adding the milk, vanilla and oil.
6. Measure out 1/3 cup portions to fry in butter in a pan until browned on both sides.