Prepare the ‘buttermilk’ mixture, by combining soy milk and vinegar in a 4 cup measuring cup, or medium mixing bowl. Slightly stir, then set aside to curdle.
In a large mixing bowl, combine flour, baking powder, salt, and sugar. Whisk well.
Add milk-vinegar mixture to the dry ingredients, then add oil, vanilla and sourdough discard.
Gently stir to combine, leaving some small lumps.
Cook in preheated waffle iron on medium-low heat, or per the manufacturers instructions.
Serve immediately or cool on wire rack. If freezing, cool completely first. Freeze and store leftovers in zip top bag.
Notes
*Tips and Substitutions*Milk– you can use a dairy milk or preferred non-dairy alternative. Preference is to soy milk because it is generally creamier/thicker.*Oil- any neutral oil would work, like canola, grapeseed, etc.*Sourdough – I have used various amounts of unfed/discard with no noticeable change from 60-100 g. Use what you’ve got!