The Overnight Waffle Method (my preference):

1. Add buttermilk and the melted and cooled butter to a large mixing bowl. It is important that you don’t add hot butter –not good for the sourdough. Then add your ripe sourdough starter and mix thoroughly (use a whisk). Sprinkle the sugar on top and whisk in your flour, a little at a time, until incorporated.
2. If necessary, use some of the (1/4 cup) reserved water to thin the batter until it resembles a traditional pancake batter (it should be thick and pour slowly from a spoon). 
3. Cover the bowl and let sit at room temperature overnight.
4. In the morning:
5. Warm your whole eggs to room temperature by letting them sit in a bowl of warm water for a few minutes. Sift the baking soda and salt onto the top of the batter. Crack the eggs and place the whites in one clean bowl and the yolks in another. Whisk the egg whites until they form stiff peaks. Lightly scramble up the egg yolks in the second bowl. Pour the yolks into the batter and gently stir through. Then, using a spatula, fold the whipped eggs whites into the mixture until just incorporated (and no more).
6. *you do not have to separate the eggs and beat the whites, but it will make the waffles lighter in texture, I think it is worth it, if you have the time.  But they are great if you skip that step 
7. Cook in your smoking hot waffle iron until done to your liking.
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   Morning of Waffles Method

1. Preheat waffle iron
2. In a large bowl whisk together flour, sugar, salt and baking soda.  In a separate bowl whisk together buttermilk and the melted but cooled butter. Then add your ripe sourdough starter and mix thoroughly (use a whisk).
3. Warm your whole eggs to room temperature by letting them sit in a bowl of warm water for a few minutes. Crack the eggs and place the whites in one clean bowl and the yolks in another. Whisk the egg whites until they form stiff peaks. Lightly scramble up the egg yolks in the second bowl. Pour the yolks into the batter and gently stir through. Then, using a spatula, fold the whipped eggs whites into the mixture until just incorporated (and no more). ***you do not have to separate the eggs and beat the whites, but it will make the waffles lighter in texture, I think it is worth it, if you have the time.  But they are great if you just add the whole eggs to the batter
4. If necessary, add 1/4 cup of water or buttermilk to thin the batter until it resembles a traditional pancake batter (it should be thick and pour slowly from a spoon). 
5. Cook in your smoking hot waffle iron until done to your liking.

Enjoy!!