Measure milk out and add the apple cider vinegar, set aside to let curdle.
In the meantime, combine flour, baking powder, cinnamon and salt in a large mixing bowl.
Add the flax seeds to the milk and mix vigorously until frothy, 30 seconds to a minute. Add mixture to the flour along with water, olive oil, maple syrup and vanilla. Mix with a wooden spoon until mostly combined then fold in the figs and walnuts until all ingredients are moistened.
Preheat waffle iron and let the batter rest. Cook according to waffle iron directions, spraying the waffle iron liberally with oil or cooking spray between each waffle is made. Garnish with extra walnuts and fig halves.